# Rasqal RDF Query Library - Release Notes

## Rasqal 0.9.33 changes

Issues Fixed:

- 0000546: Can't take query from URI when using -p
- 0000568: Filter expression with division does not work
- 0000583: CONSTRUCT halts at a template triple with unbound variable
- 0000588: roqet: select from SERVICE returns all NULLs

### SPARQL changes

Fixed `BASE` to override any API base URI.

### Datetime class changes

Fixed storing timezone minutes correctly.

### Graph pattern class changes

Added new getter functions `rasqal_graph_pattern_get_triples()`, `rasqal_literal_get_type()` and `rasqal_literal_get_language()` from Pull Request #1 by Cosmin Basca. Thanks.

### Query engine changes

Fixed the aggregation total evaluation of `AVG`.

Fixed `STRBEFORE` and `STRAFTER` evaluation to match languages if present and add the needle language to the result.

Fixed `CONCAT()` evaluation to return the correct types and languages.

Sorting now uses sort utility function `raptor_sort_r()` with context args provided by Raptor 2.0.15+ or an internal simple (not so performant) replacement, if too old.

### Query result class changes

Can write variable bindings query results in mKR relation CSV format.

### Query result class changes

Made internal changes to support reading and writing boolean result formats. That means `rasqal_query_results_formatter_read()` may now return boolean results if the formatter supports it, such as SPARQL XML.

Added `rasqal_new_query_results_from_string()` to make a query results from a string (with optional length). The results format is guessed from the input data - base_uri and string content using `rasqal_world_guess_query_results_format_name()`.

Added `rasqal_query_results_formats_check2()` deprecating `rasqal_query_results_formats_check()`. The API change is due to the return value; the result is now non-0 if the format exists.

Added `rasqal_new_query_results2()` deprecating `rasqal_new_query_results()` removing the now ignored `vars_table` parameter. A query result now manages it's own variables table.

### Results class changes

Fixed returning the correct variables count for reading SPARQL XML results sets. This caused some queries to fail if the projected variables count did not match the count in the result set. Fixes Issue #0000588

### Variables table class changes

Added `rasqal_variables_table_add2()` deprecating `rasqal_variables_table_add()`. This takes a more sensible argument style with copying the input parameters name and value, and allowing name length to be optionally given. This results in smaller calling code and better ownership semantics.

### Utility changes

`roqet(1)` now supports using a URI or local file to send to a SPARQL protocol service URI. Fixes Issue #0000546

### Other changes

Fixes to make Rasqal build in Travis CI, testing against newest and oldest raptors.

Use `__FUNCTION__` (c99) replacing `__func__` (c90) in debug macros.

Fixes in Pull Request #3 for building with icc from Sebastian Freundt. Thanks.

Many code quality fixes from clang and coverity primarily in error path cleanups (out of memory cases) and dead code.

Updated the fix-flex and fix-bison scripts to remove dead code that clang and coverity complain about.

Added new C testrunner utility to run the tests to eventually replace the (perl) improve and check-sparql scripts.

Fixed some API changelog mistakes.

Updated gcc / clang warning args used (-Wxxxx) and made multiple minor code fixes such as replacing %d with %u in debug messages or adding missing default: to switches even when all cases were covered.

Added many more internal casts to make -Wconversion happier when enabled.

## Rasqal 0.9.32 changes

Issues Fixed:

- 0000558: sparql11-update causes fallback to sparql10
- 0000560: "--with-pcre-config" documented but not supported
- 0000561: 'make check' fails; possibly because raptor2 built in separate directory
- 0000564: Rasqal fails with linker error for armv7 cross-compilation: duplicate symbol _main
- 0000567: Segfault based on documentation recommendation

### SPARQL changes

Fixed the SPARQL 1.0 and SPARQL 1.1 syntax feature checking so that language `sparql11-update` allows all SPARQL 1.1 syntax features to be used. Fixes Issue #0000558

Updated the SPARQL parser to use and require Bison 3.0 (for maintainer, building from GIT sources).

Updated the SPARQL lexer for Bison 3.0.

### API changes

Made `rasqal_new_query()` match the documentation in accepting a `NULL` name. Fixes Issue #0000567

### Configuration changes

Make ossp work as a UUID library option. `--with-uuid-library=ossp` and automatic discovery of ossp UUID now work. Fixed the inclusion of OSSP's uuid.h header.

Fix the searching for the pcre-config and libgcrypt-config configuration utilities. This probably never worked unless the envariables form (`PCRE_CONFIG` and `LIBGCRYPT_CONFIG`) were set.

Added a new internal `to-ntriples` utility to remove all use of `rapper(1)` so that the raptor utilities do not need to be available for running tests with 'make check'. Fixes Issue #0000561

Make `--with-libgcrypt-config` work.

Make `--with-pcre-config` work. Fixes Issue# 0000560

Fix noisy mhash_dir addition error; it was always added the cflags and includes even when mhash_dir was blank.

Improve raptor missing / too old error message.

### Other changes

Mention libmtwist near `--with-random-approach.` Fixes Issue #0000561

### Internal changes

Add more STANDALONE if/ifndef STANDALONE blocks around internal code or functions used in tests.

Make `rasqal_xsd_check_double_format()` an internal non-static symbol. Fixes Issue #0000564

## Rasqal 0.9.31 changes

Issues Fixed:

- 0000527: segmentation fault in roqet when making a SPARQL SERVICE query that returns an HTTP error
- 0000536: configure accepts bogus values for --with-xml2-config
- 0000537: configure pkg-config checks not overridable
- 0000538: work around MSVC 2008's inexcusable lack of stdint.h header
- 0000539: win32_rasqal_config.h doesn't work on MSVC2008

### `roqet(1)` utility changes

`roqet(1)` gains a new operating mode: reading query result files in a given format and generating them in different format. This means it can be used to convert result formats. Use this mode with the `-t RESULT-FILE` major option and `-R INPUT-RESULT-FORMAT` to set the input format. `-r OUTPUT-RESULT-FORMAT` can be used to set the output format.

      # Convert a SPARQL TSV result to XML
      $ roqet -t result.tsv -R tsv -r xml

      # Convert a SPARQL XML result (default input format) to TSV
      $ roqet -t result.srx -r tsv

Tidied and improved the help and error messages.

The utility now supports `-r simple` / `--results simple` as it says in the documentation.

The debug result format now prints 'row:' when writing. (This format has always promised it may change).

### Query result changes

Added support for reading the SPARQL 1.1 Query Results CSV and TSV Formats W3C Recommendation, 21 March 2013. Writing support already existed. This is a modular addition so the APIs that handle reading results automatically get this support.

Added `rasqal_query_results_type_label()` to get a string label for a `rasqal_query_results_type`.

### Query engine changes

Internal work to support executing the SERVICE graph pattern.

Query engine can execute the new `VALUES` graph pattern.

SPARQL lexer and parser handles `VALUES` replacing the old `BINDINGS` syntax.

Fixed crash when a SERVICE returns no rowsource. Fixes Issue #0000527

Added proper validation of xsd:double and xsd:float literal format.

Correctly handle `GROUP BY` over no data - returning one row with all bindings missing.

Literal languages are now normalized to lowercase (RDF Concepts)

### API changes

`rasqal_prefix_id()` now uses a q rather than _ to help raptor N-Triples 2008 conformance.

Improved SPARQL 1.1 query formatter to handle `VALUES` forms and to print in a prettier form with better indenting.

`rasqal_graph_pattern_op` gains `RASQAL_GRAPH_PATTERN_OPERATOR_VALUES`

`rasqal_new_rowsource_from_handler()` now allows a NULL query so that rowsources can be fully independent of a query, such as when building from a syntax string or other independent object.

`rasqal_new_rowsequence_rowsource()` now allows an empty sequence of rows.

### Portability changes

Win32 build fix patches from Michael Stahl: Fixes Issues #0000539 and #0000538

### Configuration and build changes

Added new internal convienience library libsv providing support for reading CSV and TSV files (and others potentially). Required for the updated support for reading SPARQL CSV and TSV result formats.

Added new librasqalcmdline convienience library to share code between `roqet(1)` and `check-query` (under development, not installed).

Build internal libmtwist, libgetopt (new) as libtool convienience libraries to stop automake moans about subdir-objects.

`configure` was fixed to correctly find and use OSSP libuuid even in the presence of half installed / broken UUID systems like on OSX where just the headers are present.

Fixes for building with parallel make such as `make -jN`

Fixed alignments and error paths found via clang.

`configure` now uses PKG_CHECK_MODULES() to enable overriding discovery of pkg-config if needed. Fixes Issue #0000537

Fix crash if `xml2-config(1)` when pointed at a non executable file. Patch from Michael Stahl Fixes Issue #0000536

`configure` ensures CPPFLAGS can be passed through without destruction. This helps Debian hardening

Removed the need for Perl XML::DOM to be installed in order for 'make test' to run via `check-sparql`. This requires the `roqet(1)` new '-'t mode.

Add a `configure` check for the debugging `__func__` so that on systems where it does not exist the debug macros work. It may or may not be a macro, so it cannot be tested with #ifdef in the CPP.

Improved the `configure` check for Flex to allow it to be missing for non-maintainer mode.

### Other changes

Flex code generation updates - now recommend flex 2.5.36.

Fixes in tests data for N-Triples conformance that is checked by newer Raptor.

## Rasqal 0.9.30 changes

Removed RDQL support as promised. So long and thanks for all the queries. Use SPARQL instead.

Issues Fixed:

- 0000506: configure.ac has bash -specific (non-POSIX) == syntax
- 0000511: Add support for OSSP UUID library
- 0000517: Autoconf errors when checking for several headers and cross-compiling
- 0000523: mpfr dependency

### Decimal class changes

`rasqal_xsd_decimal_is_zero()` now uses `fabs()` and an epsilon approach for C99 decimal mode.

Make `rasqal_xsd_decimal_compare()` work for C99 decimal mode.

`rasqal_xsd_decimal_compare()` and `rasqal_xsd_decimal_equals()` use Knuth's approximate equality as decribed below.

### Literal class changes

Return rdf term type string from `rasqal_literal_get_rdf_term_type()` for integer subtypes (`RASQAL_LITERAL_INTEGER_SUBTYPE`). Fixes Issue #0000519 (Redland librdf)

`rasqal_literal_to_result_term()` now returns NULL on an alloc failure.

`rasqal_new_floating_literal()` added, deprecating `rasqal_new_float_literal()` and takes the float type as an argument.

### Query engine changes

Fix some wrong data size allocs found by clang in Project rowsource.

Take more care in promoting literals to float and exceeding the range; turn them into doubles if that happens.

Floating and double comparisons and equality use a proper epsilon check using Knuth's approximate comparison approach, rather than =. Affects `rasqal_literal_as_boolean()`, `rasqal_literal_equals()`, `rasqal_xsd_decimal_compare()`, `rasqal_xsd_decimal_equals()` and other internal methods.

### Query language changes

Updated the SPARQL syntax to support `integer^^uri-ref`. Fixes Issue #0000519 (Redland librdf)

Removed RDQL support as promised. So long and thanks for all the queries. Use SPARQL instead.

### Portability changes

Test for `mpfr_snprintf()` specifically which appeared in MPFR 2.4.0. Fixes Issue #0000523

The Bison minimum version is now 2.0 (from 2004-12-25) until we hear otherwise.

Use `RASQAL_DISABLE_DEPRECATED` to flag out deprecated implementation code. Call gtkdoc-scan with the deprecated guard.

Use `#if defined(RASQAL_DEBUG)` to help portability when it's not defined.

Added good and bad cast macros for checking of type truncation. Helped remove compiler warnings.

### Configuration changes

Make `configure` handle Apple `/usr/bin/flex` which adds an extra field so awk `$NF` did not work.

`configure` now supports finding UUID support inside libc for OSX.

Fix some `configure` portability with non-POSIX bash syntax and adding some -W flags to autotool calls. Fixes Issue #0000506

Updated `autogen.sh` to abort run if a configuring program fails, generate NEWS with old timestamp if missing so automake can run and some small doc and message updates.

## Rasqal 0.9.29 changes

Rasqal fully supports SPARQL 1.0 from this release. All the approved tests pass.

Requires Raptor 2.0.7 or newer.

RDQL query language support will be removed in the next release. SPARQL has been available for 4 years and is fully supported.

Add support for SPARQL 1.1 draft `UUID()` and `STRUUID()`.

Issues Fixed:

- 0000493: Offset in sub-select results in no rows at all.
- 0000494: Temp buffer to small.
- 0000504: rasqal_regex_replace() is not public

### Datatype changes

Added a new datatype `rasqal_xsd_date` class for XSD with literal enum `RASQAL_LITERAL_DATE`, constructor `rasqal_new_xsd_date()`, destructor `rasqal_free_xsd_datetime()` and core methods `rasqal_xsd_date_to_counted_string()`, `rasqal_xsd_date_to_string()` `rasqal_xsd_date_equals()` (returning incomparible) and `rasqal_xsd_date_compare()`.

The `rasqal_xsd_datetime` and new date class above both get the same new fields for comparing datetimes and dates: `time_on_timeline` and `have_tz` to record the three timezone possibilities: none ('N'), zulu ('Z') or numeric ('Y'). A "time on timeline" value is calculated on construction and the field values are not normalized.

Added `rasqal_xsd_datetime_equals2` deprecating `rasqal_xsd_datetime_equals` and returning and incomparible flag to caller.

Added `rasqal_xsd_datetime_compare2()` deprecating `rasqal_xsd_datetime_compare()` and returning the incomparible state between datetimes. The new `rasqal_xsd_date_compare()` uses this signature.

Added new `rasqal_new_xsd_datetime_from_xsd_date()` datetime constructor to build a datetime from a date.

Correct the buffer size in `rasqal_xsd_datetime_get_seconds_as_decimal()` Fixes Issue #0000494

### Graph pattern class changes

Added `rasqal_query_graph_pattern_visit2()` deprecating `rasqal_query_graph_pattern_visit()`

### Literal class changes

Enum `rasqal_op` gains new tokens `RASQAL_EXPR_UUID` and `RASQAL_EXPR_STRUUID` for the new SPARQL 1.1 draft `UUID()` and `STRUUID` built-in functions.

`rasqal_literal_divide()` result is now a decimal if both args are integer - rule from XPath F&O;

Added support for the XSD:Date datatype with a new `rasqal_literal_type` enum value `RASQAL_LITERAL_DATE`. Updated the literal code including the constructor `rasqal_new_numeric_literal()` to auto-convert to the internal format as well as the core literal methods.

### Query engine changes

The rules for in-scope variables for `FILTER` were corrected to match the SPARQL 1.0 semantics. This fixed the last remaining failure Rasqal had for the SPARQL 1.0 approved test cases.

`DISTINCT` now compares using RDF term comparison not value comparison so now "" is distinct from ""^^xsd:string. This has a consquence of making RDQL test B-01 as failing but this is no loss. Relatedly, RDQL support will be removed in the next release.

Handle errors found in aggregation expressions following SPARQL standard.

Fix blank node generation when made in a `CONSTRUCT` to match SPARQL standard.

Make limit and offset check work properly in a subquery. Fixes Issue #0000493

Added support for executing SPARQL 1.1 draft `UUID()` and `STRUUID` using either libuuid or internal random API that backs executing `RAND()`.

### Resilience changes

Ran entire SPARQL 1.0 and 1.1 test suite through Rasqal and valgrind to check for reference loss and memory leaks. Fixed several issues in newer code.

Fixed several code issues with unused values found by clang. Or changed code that was correct to make clang moan less.

Add code marking of good and bad type casts using macros `RASQAL_GOOD_CAST` and `RASQAL_BAD_CAST` macros.

### Other changes

The `configure` test for libgcrypt as a digest backend now works; it really didn't before now. Added option `--with-libgcrypt-config=PATH` to allow selecting the path to the `libgcrypt-config`. mhash remains the preferred hash digest library as it provides more digests and is more commonly available.

`configure` now looks for libuuid with `pkg-config` to back the SPARQL 1.1 UUID generation support. The UUID backend can be selected with new configure option `--uuid-library=NAME`

Made `rasqal_regex_replace()` public with same signature as the internal API. Fixes Issue #0000504

The `tests/sparql/check-sparql` test runner was updated to understand more of the manifest vocabulary.

Building from GIT now requires automake 1.11.2+ for the `-Wextra-portability` option.

Added `-d none` to `roqet(1)` arguments so it is possible disable debug output on the command line (default).

## Rasqal 0.9.28 changes

Issues Fixed:

- 0000466: zero size calloc does not return object (src/rasqal_row.c)
- 0000467: Tests fail because diff doesn't accept -u flag
- 0000470: snprintf portability issues
- 0000471: Compile error when RASQAL_DEBUG set to > 1
- 0000474: roqet flags listed in help, but not recognised

### SPARQL changes

The language name '`sparql`' is now SPARQL 1.1

Added support for SPARQL 1.1 draft string functions `STRBEFORE()`, `STRAFTER()` and `REPLACE()`.

### Query engine changes

Add parsing and evaluation support for SPARQL 1.1 draft STRBEFORE (2 args), STRAFTER (2 args) and REPLACE (3 or 4 args). The evaluation of REPLACE currently fully works for PCRE regex with Unicode and works for POSIX regex without Unicode.

Clear `errno` before calling `strtol()` and checking the result. This caused issues when used in threaded applications, even though Rasqal is not thread-safe.

The (psuedo) random number generation now can use a variety of library random routines, defaulting to a new internal Mersenne Twister implementation - libmtwist. The choice of PRNG can be made with `configure --with-random-approach=ALGO` to pick from `mtwist` (the default), `gmp` (when GMP is available and used for decimals), `random_r()`, `rand_r()` then the portable but not so safe: `random()` and `rand()`.

### Expression class changes

Enum `rasqal_op` gains new tokens `RASQAL_EXPR_STRBEFORE`, `RASQAL_EXPR_STRAFTER` and `RASQAL_EXPR_REPLACE` for the new SPARQL 1.1 string expressions. `STRBEFORE()`, `STRAFTER()` and `REPLACE()` respectively.

Added `rasqal_new_4op_expression()` to construct 3/4-arg expressions.

### Query format and query result format changes

Added the W3C Format URIs to the JSON, XML, CSV and TSV SPARQL result formats. (Nicholas J Humfrey)

Corrected the SPARQL query output for LIMIT and OFFSET

Handle `<literal></literal>` as empty literal when reading in XML query results.

### Other changes

Use a more comprehensive `configure` build and run test for `ceil()`, `floor()` and `round()` to prevent GCC optimizing it away and getting the wrong answer when checking whether to link with -lm

Removed the obsolete -w option from the `roqet --help` message which was removed from code some time ago. Fixes Issue 0000474.

Prevent a gcc 4K stack size warning in a few tests.

Reorganized the regex code to a new regex module, adding the new function `rasqal_regex_replace()` for regex search and replace (all) backing SPARQL 1.1 `REPLACE()`

Several internal fixes for compiling with RASQAL_DEBUG > 1 (Lauri Aalto) Fixes Issue #0000471

Remove several internal uses of `snprintf()` for simple integer formatting.

The check-sparql utility used during 'make check' now sets the DIFF envariable for check tests to allow use off GNU Diff. Fixes Issue #0000467 (Peter O'Gorman / pogma)

Code style changes for calling `calloc()`.

Do not `calloc()` with 0 count for a result row - not portable. Fixes Issue #0000466 (Peter O'Gorman / pogma)

The `check_query` utility (which is still not complete) can now handle comparing query results when sorting is involved.

## Rasqal 0.9.27 changes

Issues Fixed:

- 0000127: `UNION` graph pattern support in query engine
- 0000423: SPARQL `UNION` with shared variables fails
- 0000434: `OPTIONAL` and named graphs don't mix
- 0000454: xsd:nonNegativeInteger is parsed as `RASQAL_LITERAL_QNAME` instead of `RASQAL_LITERAL_[INTEGER|UDT|INTEGER_SUBTYPE]`
- 0000459: Making a query that binds to a variable with the same name as a bnode fails

### SPARQL changes

The parser now supports the optional `SILENT` keyword for `SERVICE`.

The parser now supports the `CONSTRUCT WHERE` abbreviation, expanding the WHERE triples into a triple template with the same triples.

### Query engine changes

sub-`SELECT`s are now supported including those that contain sorting, grouping, limiting and offset as well as projection.

`CONSTRUCT` works when working over a query with optionals. It previously stopped returning results at the first unbound variable value.

`OPTIONAL`, sub-graph pattern groups and `UNION` fully execute correctly. Fixes were made to the variable scoping and join operations.

A lot of refactoring was done to provide the structure to enable sub-`SELECT` to be turned into a query algebra structure and executed.

An entirely new variable scoping algorithm was implemented to properly compute where a variable is assigned; the assumption was removed that a variable with a given name can only be bound in one place.

Several bugs were fixed in the join implementation which affected the sub-graph pattern grouping (natural join) and optional (left join).

Pulled new internal function `rasqal_query_results_formatter_get_read_rowsource()` out of `rasqal_service_execute()` to provide the structure for executing `SERVICE` queries in the query engine.

### Literal class changes

`rasqal_new_numeric_literal_from_long()` added to make an integer or decimal literal depending if it fits in range.

`rasqal_xsd_decimal_get_long()` added to convert an arbitrary precision decimal to a C long with an overflow error flag.

xsd:integer subtypes are stored and printed correctly. Fixes Issue #0000454.

### Query class changes

`rasqal_query_get_distinct()` added to get the distinct flag from `SELECT DISTINCT ...` queries.

`rasqal_query_set_wildcard()` added to set the '*' flag for `SELECT *` queries

`rasqal_query_has_variable2()` added with variable type arg deprecating `rasqal_query_has_variable()`. Note the warning about using `RASQAL_VARIABLE_TYPE_UNKNOWN` is ambiguous.

Deprecated `rasqal_query_has_variable()` for the above. Lookup by any type.

`rasqal_query_set_variable2()` added with type arg deprecating `rasqal_query_set_variable()`. Note the warning about using `RASQAL_VARIABLE_TYPE_UNKNOWN` is ambiguous.

Deprecated `rasqal_query_set_variable()` for above. Lookup by any type.

### Query result format changes

The CSV and TSV query result formats (names `csv` and `tsv` respectively) were altered to match the editor's draft SPARQL 1.1 Query Results CSV and TSV Formats which includes no header line, no result number and implementing the specified quoting and end of lines in the specification.

### Variable class changes

`rasqal_variables_table_add_variable()` added to add an existing variable to a variables table.

`rasqal_variables_table_get_by_name()` added with variable type arg.

`rasqal_variables_table_contains()` added to check if a variable with the given type and name is in the variables table.

### `roqet(1)` utility changes

Correctly order the help so the `-d/--dump-query` value list appears after the option description.

### Porting changes

Several patches were made to aid compiling on MS Windows were applied based on those made by the KDE Emerge scripts to build KDE on windows. This includes a native replacement for the missing gettimeofday() and timegm() functions. MS Windows remains an unsupported target.

### Other changes

The minimum Raptor version needed is now 2.0.4 for the `raptor_bnodeid_ntriples_write()` function.

The test runner was fixed to fail the suite when there are failures as well as expected failures.

Code style change and cleanup for alloc/free macros. New code style:

1. `var = RASQAL_CALLOC(type, nmem, size)`
   Prefering:
   `var = RASQAL_CALLOC(type, 1, sizeof(*var))`
   when nmem = 1
2. `var = RASQAL_CALLOC(type, size)`
3. `RASQAL_FREE(type, var)`

The consequence here is allocs that mostly fit into 1 line without so much boilerplate and duplication of types. The `RASQAL_MALLOC` and `RASQAL_CALLOC` macros now do the cast to the return type. `RASQAL_FREE` takes the object type too but always casts arg to void This

Code style change for allocating strings:

1. `len = strlen(); malloc(..., len + 1)`
2. and `memcmp(..., len + 1)`

Expanded GCC warnings to take advantage of newer analysis which found several issues:

- Use of int for storing string and buffer lengths: replaced many internal uses with the correct size_t for length computations.
- Use of int for storing time: replaced with time_t that may be larger
- Use of `void*` for pointer differences: replaced with `ptrdiff_t` where necessary.
- Precision truncation between int and long, size_t.
- Precision truncation between float and double.

Made several internal functions to improve the above. There remain some int / size_t errors in the public API that will need new API functions to properly fix for 64-bit machines dealing with strings more than >32bits in length; which should be rare.

Reduced Rasqal's call stack size by ensuring all I/O buffers are dynamically allocated.

`configure` now always checks for where `ceil()`, `floor()` and `round()` can be found: in libc or libm.

The `configure` default for `--enable-maintainer-mode` no longer enables the debugging symbols. These can be added with `--enable-debug`

The `configure` gains an option `--with-gmp=`PATH to set the installation path of the GNU Multiple Precision Arithmetic Library (GMP) if it is not in the standard lib/include prefix.

## Rasqal 0.9.26 changes

Issues Fixed:

- Issue #0000430: Incorrect HTML generated with unknown literal types
- Issue #0000431: Only a limited number of literal datatypes are displayable in a HTML format.
- Issue #0000436: queries involving calculations with large numbers return incorrect results unless scientific notation is used
- Issue #0000438: timegm not available on solaris
- Issue #0000439: warning when variable is not selected makes 4store tests to fail
- Issue #0000446: rasqal may require -lm for floor, ceil, round on some systems and architectures

### SPARQL 1.1 Query draft language changes

Added support for SPARQL 1.1 message digest functions `MD5()`, `SHA1()`, `SHA224()`, `SHA256()`, `SHA384()` and `SHA512()`

### Query engine changes

Many internal query engine changes to more accuractly compute variable scope, use and binding to better support more complex queries with scopes such as `UNION` (now mostly working) and sub-`SELECT` (execution is not yet supported).

Added `rasqal_world_set_warning_level()` to set the query warning level in the 0...100 range where 0 is no warnings, 50 is the default and 100 is all warnings.

Query errors now fail with regular errors not fatal errors that `abort()`. Query parsing errors are not work killing the process. Also adjusted some error paths to prevent reporting 2 errors at once.

`rasqal_op` enumeration gains values `RASQAL_EXPR_MD5`, `RASQAL_EXPR_SHA1`, `RASQAL_EXPR_SHA224`, `RASQAL_EXPR_SHA256`, `RASQAL_EXPR_SHA384` and `RASQAL_EXPR_SHA512` for message digest expressions corresponding to SPARQL 1.1 message digest functions.

Added message digest support either built with internal MD5 and SHA1 which are always available, or with libmhash which provides the full list of message digests that SPARQL 1.1 requires (and is optimized).

Make `ROUND()` work with XSD Decimal when compiled against GNU MP.

Check for overflow when converting a string to int and if resulting long won't fit in an int, turn it into a decimal. Fixes Issue #0000436.

Removed Query Engine V1 that was long disabled. `configure` loses the `--with-query-engine-version` option.

### Query results formatter class changes

Fixed HTML query results generating invalid HTML. Fixes Issue #0000430

Support writing additional literal types in HTML query results. Fixes Issue #0000431

The JSON query result format now accepts the `application/sparql-results+json` mime type, as specified in the Serializing SPARQL Query Results in JSON W3C WG Note.

### `roqet(1)` utility changes

Added options `-W` / `--warnings` level (default 50) to set the warning level and `-E` to ignore errors.

### Other changes

`configure` gains a `--enable-debug` option to enable or disable the debugging messages. Useful for when building using `autogen.sh` from GIT.

Removed internal test/debug 'redland' triples store that has not worked for some time. Removed the `--with-triples-source` and `--with-redland-config` options from `configure`.

Add a portable version of `timegm()` when it is not present in the system (such as Solaris). Fixes Issue #0000438.

Added `configure` tests for `ceil()`, `floor()` and `round()` that look for them in libc or libm. Fixes Issue #0000446.

Fixed up several code paths with problems found by clang, mostly unused variables, unnecessary calculations but a couple of bad accesses.

## Rasqal 0.9.25 changes

Issues Fixed:

- Issue #0000421: Use raptor_syntax_description_validate() to validate Query Results formats
- Issue #0000427: INSERT/DELETE with """ quoting doesn't quite work
- Issue #0000428: @lang doesn't work with """:

### SPARQL 1.1 Query draft language changes

Added support for SPARQL 1.1 numeric functions `ABS()`, `ROUND()`, `CEIL()` and `FLOOR()`.

Added support for SPARQL 1.1 `BIND(expr as ?var)` using existing `RASQAL_GRAPH_PATTERN_OPERATOR_LET`.

Added support for SPARQL 1.1 `CLEAR` and `DROP` to use optional `SILENT` keyword.

Added support for SPARQL 1.1 `RAND()` along with a query API feature for user setting of the random seed.

Added support for SPARQL 1.1 TZ()

Fixed SPARQL 1.1 `ENCODE_FOR_URI()` to not preserve language and datatype of input.

Fixed support for SPARQL 1.1 `BNODE()` to work with no argument given.

Fixed SPARQL 1.1 `GROUP BY` to allow an optional `AS ?var`.

Fixed support for """-quoted and '''-quoted strings not over-quoting and adding support for optional language. Fixes Issue #0000427 and Issue #0000428.

### DateTime class changes

Added `rasqal_xsd_datetime_get_tz_as_counted_string()` to get back the timezone string component of a datetime.

### Datatype class changes

`rasqal_xsd_format_double()` now correctly formats numbers that have no trailing 0s.

### Decimal class changes

Added `rasqal_xsd_decimal_abs()`, `rasqal_xsd_decimal_round()`, `rasqal_xsd_decimal_ceil()` and `rasqal_xsd_decimal_floor()` to support the ABS(), ROUND(), CEIL() and FLOOR() functions for decimals.

### Expression class changes

rasqal_op gains `RASQAL_EXPR_ABS`, `RASQAL_EXPR_ROUND`, `RASQAL_EXPR_CEIL` and `RASQAL_EXPR_FLOOR` for numeric operations, `RASQAL_EXPR_RAND` for SPARQL 1.1 `RAND()` and `RASQAL_EXPR_TZ` for SPARQL 1.1 TZ() timezone accessor.

Added an evaluation context structure `rasqal_evaluation_context` for the information needed to evaluate any `rasqal_expression` tree. This makes expression evaluation independent of a query, but still tied to a rasqal world and (via variables) a variables table. Added constructor `rasqal_new_evaluation_context()` to set the locator and flags, destructor `rasqal_free_evaluation_context()`, method `rasqal_evaluation_context_set_base_uri()` to set/reset the shared reference to the context base URI and method `rasqal_evaluation_context_set_rand_seed()` to set the random seed for the evaluation.

Added `rasqal_expression_evaluate2()` taking just an expression and an evaluation context.

`rasqal_expression_evaluate()` is deprecated for the above.

Added new method `rasqal_xsd_datetime_get_tz_as_counted_string()` for executing `RASQAL_EXPR_TZ` for SPARQL 1.1 TZ().

### Query Engine changes

Initialise seed for RAND() from either a mixture of system sources or from a value set by user. The user value can be set with new query feature `RASQAL_FEATURE_RAND_SEED`. Uses `rasqal_evaluation_context_set_rand_seed()` on the query's internal evaluation context.

Enable `rasqal_query_set_store_results()` to actually work after a query prepare.

Handle evaluation of `FILTER` over an empty inner graph pattern such as in a query like `ASK WHERE { FILTER ( TRUE ) }`

Ignore errors in executing SPARQL 1.1 project expression `AS` variables.

Update `rasqal_literal_as_boolean()`, `rasqal_literal_as_integer` and `rasqal_literal_as_floating` when evaluating NULL to return a type error not an assertion failure or abort (in debug mode).

Change internal error handling to separate a NULL return from an error return when evaluating expressions. Updated lots of callers of expression evaluation to handle a NULL expression response. Needed since now NULL is a valid expression evalution in some cases; like STRLANG() on non-simple literals.

Updated to use `rasqal_evaluation_context` for expression evaluation.

Handle support executing empty graph patterns such as in queries like `SELECT (expr AS ?var) WHERE {}` which just evaluates `expr` and returns a single row with a single result.

### Query Result Formatter class changes

Handle NULL values for RDF and Tables results.

### Other changes

Added `rasqal_world_get_query_language_description()` to get a description of a query language replacing and deprecating `rasqal_languages_enumerate()`.

More fixes to check-query test script.

Make GPL V2 or newer explicit in LICENSE.html.

## Rasqal 0.9.24 Changes

### SPARQL 1.1 Update draft Language changes

Added support for `CLEAR` and `DROP` applying to more than one graph. The options are now: just default graph with `DEFAULT`, all named graphs with `NAMED` and all graphs with `ALL`.

Added support for optional `SILENT` flag before most update operations.

Added support for `ADD`, `MOVE` and `COPY` operations which both operate between two graphs - either named or default. The source graph is stored in the update structure `graph_uri` field and the destination graph in the `document_uri` field; the names have no meaning here since both are graphs and a NULL value signifies the default graph.

Added support for `DELETE WHERE {}` writing the triple results into the `delete_templates` field of the update structure.

Added support for multiple update operations in one 'query' separated by ';'.

`GROUP_CONCAT()` now sets the `RASQAL_EXPR_FLAG_AGGREGATE` rasqal_expression flag like the other builtin aggregate expressions.

### Query Engine changes

Fixed a few memory leaks in aggregate operation with `GROUP` and with `HAVING`.

### Literal API changes

Fixed a memory leak with datetime literals.

### Update API changes

`rasqal_update_type` gains new enum values `RASQAL_UPDATE_TYPE_ADD`, `RASQAL_UPDATE_TYPE_MOVE` and `RASQAL_UPDATE_TYPE_COPY` for the SPARQL 1.1 Update ADD, MOVE and COPY operations respectively.

Added enum `rasqal_update_graph_applies` to specify scope that update applies to beyond one graph to either just the default graph, to all named graphs or to all graphs. Applies to CLEAR and DROP operations only

### Other changes

Make all object destructors simply return on a NULL object pointer. This was already done but with different code styles.

## Rasqal 0.9.23 Changes

Fixed Issues:

- 0000407: ORDER BY does not appear to handle undefined values correctly
- 0000414: Type of operation->insert_templates depends on Update syntax
- 0000415: Graph pattern operator not correctly filled out in SPARQL 1.1 Updates
- 0000417: SELECT DISTINCT sometimes returns duplicates

### Graph pattern class changes

Added `rasqal_graph_pattern_get_flattened_triples()` to flatten a recursive basic/graph graph pattern to a sequence of triples or triple patterns (have variables).

### SPARQL Query Language changes

Fix the parsing of SPARQL 1.1 Update draft INSERT and DELETE to return sequences of triples in the insert_templates and delete_templates fields as documented. It would previously sometimes return that but mostly return a sequence of recursive graph patterns.

When a syntax error happens due to use of a language feature, do proper error handling (no aborting) and clean up parsing resources.

## Rasqal 0.9.22 Changes

> WARNING: ABI AND API CHANGED IN THIS RELEASE.

> This means: functions, enums and types were added, removed and changed.

> Consequently the shared library major soname version has changed from 2 to 3.

The main changes in this release were to add more draft SPARQL 1.1 features and to use Raptor V2.

Rasqal now depends on Raptor V2. Raptor V1 is not supported. The minimum Raptor2 version is 2.0.0.

Given the the large dependency change above that requires recompiling with some breakage, this release makes an ABI and API break. All deprecated functions, types and other deprecated functionality have been removed. The libtool library version was bumped to 3.0.0. The detailed API changes are described in the Changes section of the Rasqal reference manual.

### Query Engine Changes

Query engine initialises start of execution datetime to enable a `NOW()` function to provide a stable value during a single execution.

### Query Language Changes

Split query language support into more languages with aliases:

- `sparql` (and alias `sparql10`): SPARQL 1.0 query with no 1.1 features.
- `sparql11-query:` SPARQL 1.1 query.
- `sparql11-update:` SPARQL 1.1 update.
- `sparql11:` SPARQL 1.1 with both query and update.
- `laqrs:` LAQRS experimental language with all of above plus experiments.

### LAQRS Query Language changes

Added experimental datetime builtin methods:

- `NOW()` / `CURRENT_DATETIME()`: Synonyms to return an XSD datetime for the current wall clock date and time. At the first execution / preparation of the query, the value is set as a constant throughout the life of the query execution.
- `FROM_UNIXTIME()`: turns an integer value into an XSD DateTime.
- `TO_UNIXTIME()`: turns an XSD DateTime into an integer value.

These functions are not opposites and will not roundtrip date times since they do not take into consideration leap seconds or daylight saving time changes.

### SPARQL Query Language changes

Fixed SPARQL 1.1 draft `isNUMERIC()` which was stored wrongly in the parse tree as `RASQAL_EXPR_ISLITERAL`.

Added SPARQL 1.1 draft dateTime accessor builtin functions along with expression execution support.

- `DAY()`
- `HOURS()`
- `MINUTES()`
- `MONTH()`
- `SECONDS()`
- `TIMEZONE()`
- `YEAR()`

Added SPARQL 1.1 draft string builtin functions along with expression execution support.

- `CONCAT()`
- `CONTAINS()`
- `ENCODE_FOR_URI()`
- `LCASE()`
- `STRENDS()`
- `STRLEN()`
- `STRSTARTS()`
- `SUBSTR()`
- `UCASE()`

### Data Graph class changes

Removed deprecated `rasqal_new_data_graph()` constructor replaced by `rasqal_new_data_graph_from_uri()` with additional arguments.

### Datetime class changes

Added `rasqal_xsd_datetime` class to the public API implementing the XML Schema datatypes (XSD) dateTime with microsecond accuracy (where present) and timezone offsets of minutes accuracy. The new class has constructors:

- `rasqal_new_xsd_datetime()`
- `rasqal_new_xsd_datetime_from_timeval()`
- `rasqal_new_xsd_datetime_from_unixtime()`

destructor:

- `rasqal_free_xsd_datetime()`

and methods:

- `rasqal_xsd_datetime_compare()`
- `rasqal_xsd_datetime_equals()`
- `rasqal_xsd_datetime_get_as_timeval()`
- `rasqal_xsd_datetime_get_as_unixtime()`
- `rasqal_xsd_datetime_get_seconds_as_decimal()`
- `rasqal_xsd_datetime_get_timezone_as_counted_string()`
- `rasqal_xsd_datetime_set_from_timeval()`
- `rasqal_xsd_datetime_set_from_unixtime()`
- `rasqal_xsd_datetime_to_counted_string()`
- `rasqal_xsd_datetime_to_string()`

### Expression class changes

`rasqal_expression_evaluate()` now evaluates the new SPARQL 1.1 draft strings and datetime builtin functions.

`rasqal_op` gains new values for SPARQL 1.1 builtin functions:

- `RASQAL_EXPR_CONCAT`
- `RASQAL_EXPR_DAY`
- `RASQAL_EXPR_HOURS`
- `RASQAL_EXPR_MINUTES`
- `RASQAL_EXPR_MONTH`
- `RASQAL_EXPR_SECONDS`
- `RASQAL_EXPR_TIMEZONE`
- `RASQAL_EXPR_YEAR`

`rasqal_op` gains new values for LAQRS experimental builtin functions:

- `RASQAL_EXPR_CURRENT_DATETIME`
- `RASQAL_EXPR_FROM_UNIXTIME`
- `RASQAL_EXPR_NOW`
- `RASQAL_EXPR_TO_UNIXTIME`

`rasqal_new_function_expression()` constructor gained `params` and `flags` arguments to handle aggregate expressions. This was renamed from `rasqal_new_function_expression2()`.

Removed deprecated `rasqal_new_function_expression2()` replaced by `rasqal_new_function_expression()` with same arguments.

Added constructor `rasqal_new_expr_seq_expression()` replacing `rasqal_new_coalesce_expression()` and taking an op argument to use for different expression operations.

Removed method `rasqal_new_coalesce_expression()` replaced by `rasqal_new_expr_seq_expression()` with additional op argument.

`rasqal_expression_evaluate()` evalutes experimental LAQRS datetime builtin methods `NOW()`, `CURRENT_DATETIME()`, `FROM_UNIXTIME()` and `TO_UNIXTIME()`.

Fixed `RASQAL_EXPR_DATATYPE` expression execution to return the result rather than the function argument.

### Literal class changes

Support XSD dateTime literals. `rasqal_literal` value union gains a datetime field.

Added new constructor `rasqal_new_datetime_literal_from_datetime()` to make a datetime literal.

`rasqal_literal_set_typed_value()` turns xsd:dateTime literals into `rasqal_xsd_datetime` objects.

`rasqal_literal_equals_flags()` and `rasqal_literal_compare()` now use `rasqal_datetime` equality and comparison methods.

Added new accessor `rasqal_literal_as_counted_string()` get the string version of its and its length, letting the caller avoid strlen() on the result.

### Query class changes

Added method `rasqal_query_get_result_type()` to get the expected result type based on the query structure.

Added method `rasqal_query_set_store_results` to enable storing results of an execution.

Removed deprecated methods: `rasqal_query_set_fatal_error_handler()` `rasqal_query_set_error_handler()` `rasqal_query_set_warning_handler()` replaced by using `rasqal_world_set_log_handler()` calling a raptor_log_handler.

Removed deprecated methods: `rasqal_query_set_default_generate_bnodeid_parameters()` `rasqal_query_set_generate_bnodeid_handler()` that have moved to methods on the rasqal_world object: `rasqal_world_set_default_generate_bnodeid_parameters()` and `rasqal_world_set_generate_bnodeid_handler()` respectively.

`rasqal_query_add_data_graph()` was altered to take a single `rasqal_data_graph` argument instead of uri, name and flags. This was renamed from `rasqal_query_add_data_graph2()`.

Removed `rasqal_query_add_data_graph2()` replaced by `rasqal_query_add_data_graph()` with same arguments.

### Query Results class changes

Added support for query result rewinding, if the results were stored in execution via `rasqal_query_set_store_results()`, new method `rasqal_query_results_rewind()` may be called to reset back to the initial binding result.

Added `rasqal_query_results_get_row_by_offset()` to access stored query result rows if storing results was enabled by `rasqal_query_set_store_results()`.

Enum `rasqal_query_results_type` gains value `RASQAL_QUERY_RESULTS_UNKNOWN` for when a query result type is unknown or yet to be determined.

Added method `rasqal_query_results_get_type()` to get the query result type.

`rasqal_query_results_read()` was altered to take a name, mime_type, format_uri, base_uri args instead of format_uri, base_uri. This was renamed from `rasqal_query_results_read2()`.

Removed `rasqal_query_results_read2()` replaced by `rasqal_query_results_read()` with the same arguments.

`rasqal_query_results_write()` was altered to take a name, mime_type, format_uri, base_uri args instead of format_uri, base_uri. This was renamed from `rasqal_query_results_write2()`.

Removed `rasqal_query_results_write2()` replaced by `rasqal_query_results_write()` with same arguments.

### Query Results Formatter class changes

Added new constructor `rasqal_new_query_results_formatter_for_content()` to get a query result formatter based on guessing from format URI, name, mime type, some initial content or an identifier using `rasqal_world_guess_query_results_format_name()`.

Removed `rasqal_new_query_results_formatter2()` constructor replaced by `rasqal_new_query_results_formatter()` constructor.

Removed deprecated `rasqal_new_query_results_formatter_by_mime_type()` replaced by `rasqal_new_query_results_formatter_for_content()` with additional arguments.

Added world method `rasqal_world_guess_query_results_format_name()` to guess format based on format URI, mime type, some initial content or an identifier.

Added guessing based on identifier/filename suffix for the 'rdf' (.rdf), 'turtle' (.ttl, .n3) and 'xml' (.srx) formatters.

Added reading support for the existing 'rdfxml' and 'turtle' query result formatters to make both of these read/write formatters.

Added `rasqal_world_get_query_results_format_description()` to get the list of query results format syntaxes using a `raptor_syntax_description` structure. This replaced and deprecates the `rasqal_query_results_formats_enumerate()` and `rasqal_query_results_formatter_get_mime_type()` methods.

This change allows the query result formats to be identified and discovered by multiple names (aliases) and URI strings when using the `rasqal_new_query_results_formatter2()` constructor.

`rasqal_new_query_results_formatter()` constructor was altered to take name, format type, format URI args instead of just name, format URI. This was renamed from `rasqal_new_query_results_formatter2()`.

`rasqal_query_results_formats_check()` was altered to take name, format URI, mime_type flags instead of name, uri and type. This was renamed from `rasqal_query_results_formats_check2()`.

Removed `rasqal_query_results_formats_check2()` replaced by `rasqal_query_results_formats_check()` with the same arguments.

Removed `rasqal_query_results_formats_enumerate()` replaced by `rasqal_world_get_query_results_format_description()` using static syntax description approach.

Removed `rasqal_query_results_formatter_get_mime_type()` replaced by using fields of `raptor_syntax_description` structure returned by `rasqal_world_get_query_results_format_description()`.

### Variable class changes

Removed deprecated constructors `rasqal_new_variable_typed()` `rasqal_new_variable()` replaced by the `rasqal_variables_table_add()` method on a variables table to create and add a variable in a context.

### Other changes

Replaced all uses of `strcpy()` with `memcpy()` and known lengths.

Refactored huge `rasqal_expression_evaluate()` switch and case code into sub-methods preparing for possible later change to a jump table based on expression operation.

`rasqal_xsd_decimal_as_string()`: Fix decimal to string xsd lexical form details: rounding precision, format details (such as 0.0 not 0.0E0) when built with MPFR or GMP instead of the (imprecise) `double` implementation.

Fix xsd double lexical form formatting to use capital E.

Started creating `check-query` query test runner utility.

## Rasqal 0.9.21 Changes

The main changes in this release are to add support for features of SPARQL 1.1 Query W3C working draft of 14 October 2010:

- Executing grouping of results: `GROUP BY`
- Executing aggregate expressions: `AVG`, `COUNT`, `GROUP_CONCAT`, `MAX`, `MIN`, `SAMPLE`, `SUM`
- Executing filtering of aggregate expressions: `HAVING`
- Parsing of new syntax: `BINDINGS`, `isNUMERIC()`, `MINUS`, sub `SELECT` and `SERVICE`.

Fixed Issues:

- 0000388: Can only write JSON format for variable binding and boolean results

### Query Engine changes

Support executing new SPARQL 1.1 draft function `isNUMERIC()`.

Support executing built-in aggregate expressions:

- `AVG(expr)`
- `COUNT(*)` and `COUNT(expr)`
- `GROUP_CONCAT(expr)` with optional `;separator = 'string'`
- `MAX(expr)`
- `MIN(expr)`
- `SAMPLE(expr)`
- `SUM(expr)`

with and without `DISTINCT` across the arguments.

Support executing grouping of results with `GROUP BY` (or implicitly if aggregate function was given) and `HAVING` to filter groups.

### LAQRS Query Language changes

Explain more carefully that `EXPLAIN` and `COALESCE()` are LAQRS only and remain experimental.

### SPARQL Query Language changes

Separate SPARQL 1.0 and SPARQL 1.1 draft language names giving query languages sparql (with alias sparql10 for SPARQL 1.0), sparql11 for SPARQL 1.1 and laqrs for experiments. The sparql name without a version currently points to SPARQL 1.0 but over time will advance to be SPARQL 1.1

Added support for parsing (not executing) new SPARQL 1.1 draft tokens: `BINDINGS` for variable bindings, `UNDEF`, `SERVICE` and `MINUS`.

Added support for parsing and executing new SPARQL 1.1 draft `isNUMERIC()` expression.

Added support for parsing (not executing) new SPARQL 1.1 draft sub-`SELECT` queries.

Support for parsing and executing built-in (not user) aggregate expressions: `AVG(expr)`, `COUNT(*)` and `COUNT(expr)`, `GROUP_CONCAT(expr)` with optional `;separator = 'string'`, `MAX(expr)`, `MIN(expr)`, `SAMPLE(expr)` and `SUM(expr)` with and without `DISTINCT` across the arguments.

Added support for executing grouping of results with `GROUP BY` (or implicitly if aggregate function was given) and `HAVING` to filter groups.

### Bindings class changes

Added a class to support for SPARQL 1.1 draft `BINDINGS` in a query specifying a set of variable bindings and a sequence of rows of values to bind to them. Intended for applying to a SPARQL 1.1 draft query `SERVICE` call.

Added bindings class rasqal_bindings with constructor `rasqal_new_bindings`, destructor `rasqal_free_bindings()` and method `rasqal_bindings_print()`

Added accessor methods for getting bindings variables and rows `rasqal_query_get_bindings_variables_sequence()`, `rasqal_query_get_bindings_variable()`, `rasqal_query_get_bindings_rows_sequence()` and `rasqal_query_get_bindings_row()`

### Data Graph class changes

Turn a data graph into a reference-counted class and add support for specifying the format of a data graph for parsing after retrieval.

typedef `rasqal_data_graph` gains new optional format_type, format_name and format_uri fields for describing the format of the graph an optional uri field for base URI and a usage field.

Added constructor `rasqal_new_data_graph_from_uri()` with format_type, format_name and format_uri args deprecating rasqal_new_data_graph() without them, which always guessed the format.

Added constructor `rasqal_new_data_graph_from_iostream()` taking a raptor_iostream arg to allow getting data graphs from non-URIs which could be strings, memory etc.

Added copy constructor `rasqal_new_data_graph_from_data_graph()` for data graphs.

### Expression and literal class changes

Added support for SPARQL 1.1 draft `isNUMERIC()` expressions. The `rasqal_op` gains a new `RASQAL_EXPR_ISNUMERIC` value.

Added `rasqal_expression_op_label()` to return the label for an expression operation.

Added `rasqal_expression_compare()` to compare literals.

Added `rasqal_expression_is_aggregate()` to test if an expression is an aggregate one - has an aggregate operation or user-defined function.

Added `rasqal_literal_type_label()` to return the label for a literal type.

### Graph pattern class changes

`rasqal_graph_pattern_operator` enumeration gains new values for SPARQL 1.1 draft features: `RASQAL_GRAPH_PATTERN_OPERATOR_SELECT` for sub-SELECT, `RASQAL_GRAPH_PATTERN_OPERATOR_SERVICE` for service binding and `RASQAL_GRAPH_PATTERN_OPERATOR_MINUS` for minus operation between graph patterns.

Added new constructor `rasqal_new_single_graph_pattern()` for use with service and minus graph patterns.

Added `rasqal_graph_pattern_get_variable()` method to get the variable for SPARQL 1.1 draft `BIND` and LAQRS `LET` graph patterns.

Added `rasqal_graph_pattern_get_service()` method to get the service object for SPARQL 1.1 draft `SERVICE` graph pattern.

### Query class changes

Added `rasqal_query_add_data_graph2()` to add a previously constructed data graph to a query deprecating `rasqal_query_add_data_graph()` that did construct and add in one go.

Added `rasqal_query_add_data_graphs()` to add a sequence of data graphs to a query.

Added `rasqal_query_add_data_graph_from_iostream()` using new `rasqal_new_data_graph_from_iostream()`.

Note in the docs for `rasqal_query_set_limit()` and `rasqal_query_set_offset()` that with the new query engine approach, you cannot set the limit or offset until the query is prepared which is after parsing.

### Query results class changes

Add a formatter to write a variable bindings query results in Turtle format with the schema used for the W3C DAWG and SPARQL Working group test cases.

`rasqal_query_results_formats_check2()` added with new flags arg for asking for a format to read or write, deprecating `rasqal_query_results_formats_check()` without it.

### Row class changes

The `rasqal_row` gains a `group_id` field for returning group boundaries. Change of groups should be detected by a change in IDs between rows.

### Service class changes

Added a `rasqal_service` class for executing remote queries against a SPARQL HTTP protocol endpoint and getting back a query results set. The data graphs attached get turned into `default-graph-uri` and `named-graph-uri` URI parameters to the request.

Added constructor `rasqal_new_service()`, destructor `rasqal_free_service()` and methods `rasqal_service_set_www()` to set the WWW object `rasqal_service_set_format()` to set the accept request header and `rasqal_service_execute()` to execute the query returning the results.

### Triples source class changes

Add a way for a triples source factory to return meaningful errors by adding a new `init_triples_source` factory method to the `rasqal_triples_source_factory` that takes a `rasqal_triples_error_handler` callback. The `RASQAL_TRIPLES_SOURCE_FACTORY_MAX_VERSION` is now 2 and ranges 1 to 2 are supported.

Add a way for a triples source to indicate support for optional features by adding a `support_feature` method toe the `rasqal_triples_source` structure. The `RASQAL_TRIPLES_SOURCE_MAX_VERSION` is now 2 and ranges 1 to 2 are supported.

Added enum `rasqal_triples_source_feature` with value `RASQAL_TRIPLES_SOURCE_FEATURE_IOSTREAM_DATA_GRAPH` to indicate a triple source supports reading data graphs from a `raptor_iostream`.

### Variable class changes

Now a reference-counted class.

Deprecated `rasqal_new_variable()` and `rasqal_new_variable_typed()` for `rasqal_variables_table_add()`.

### Internal changes

All destructors accept NULL objects and do nothing.

Add a Raptor V2-style raptor_syntax_description data model to Rasqal and use it to initialise query languages. It is not currently exposed in the API and may not be until Rasqal requires Raptor V2 when it can share code.

Added an internal `rasqal_bindings` structure for SPARQL 1.1 `BINDINGS`.

Add an internal query results modifiers structure rasqsal_solution_modifier class for use in storing group by, having, limit, offset information which together SPARQL 1.1 documentationc calls modifiers.

Added rowsources for grouping, executing aggregated queries across groups, having filters per group. Modified the projection rowsource to handle aggregation.

### `roqet(1)` utility changes

Added support for serializing to graphs or bindings with the same Raptor serializer / Rasqal result formatter name such as for example 'json'.

Added `-F NAME` option for specifying the data graph format; otherwise Raptor uses the guessing mechanism.

Added support for reading a data graph from standard input (stdin) when the `-D` / `--data` , `-G` / `--name` or `-s` / `--source` options are used with value `'-'`.

Added `-p` / `--protocol` SERVICE-URI option to execute a remote query at a SPARQL HTTP protocol URI. This is used with `-e` query string to specify the query to execute remotely.

### Configuration and build changes

Use AC_LANG_SOURCE for gcc flag test.

### Other changes

The srxread and srxwrite example programs now build when Rasqal is configured and built with raptor V2.

## Rasqal 0.9.20 Changes

The main changes in this release are:

- Support more SPARQL 1.1 Query and Update draft syntax and some execution semantics for new built-in expressions.
- Support building with Raptor V2 API as well as Raptor V1 API. The Raptor V2 API is only used if `--enable-raptor2` is given to `configure`.

Fixed Issues:

- 0000352: CONSTRUCT with a LIMIT doesn't limit query results
- 0000353: CONSTRUCT with an ORDER always(?) returns an empty graph
- 0000354: Comparing xsd:int and xsd:integer fails in SPARQL
- 0000360: [PATCH] HTML Table results format
- 0000374: Solaris 10 'make check' failures
- 0000377: Cannot format results in roqet
- 0000378: Crash when cleaning up after a failed query containing unsupported syntax

### Query API changes

Moved generate blank node ID functionality to world class. Deprecated `rasqal_query_set_default_generate_bnodeid_parameters()` for `rasqal_world_set_default_generate_bnodeid_parameters()`. Deprecated `rasqal_query_set_generate_bnodeid_handler()` for new function (with different handler signature) `rasqal_world_set_generate_bnodeid_handler()`.

Added `rasqal_query_get_having_conditions_sequence()` and `rasqal_query_get_having_condition()` for getting access to the HAVING expression list in a query.

### Expression and literal class changes

Added new literal type `RASQAL_LITERAL_INTEGER_SUBTYPE` to let subtypes of `xsd:integer` work in data and expression evaluation.

Add support for SPARQL 1.1 draft `FILTER` expression operators including execution in the expression evaluation and writing the expression as SPARQL:

New `rasqal_op` enum | SPARQL 1.1 expression
--- | ---
`RASQAL_EXPR_IF` | IF(condition expression, expr if true, expr if false)
`RASQAL_EXPR_URI` | URI(uri string)
`RASQAL_EXPR_IRI` | IRI(iri string)
`RASQAL_EXPR_STRLANG` | STRLANG(literal string, language string)
`RASQAL_EXPR_STRDT` | STRDT(literal string, datatype URI)
`RASQAL_EXPR_BNODE` | BNODE() and BNODE(string)
`RASQAL_EXPR_IN` | Expr IN ( list )
`RASQAL_EXPR_NOT_IN` | Expr NOT IN ( list )

Added expression evaluation and expression formatting support for the above new (non-aggregate) expression operations in: `rasqal_expression_clear()`, `rasqal_expression_visit()`, `rasqal_expression_write()`, `rasqal_expression_print()`, `rasqal_expression_is_constant()` and `rasqal_query_write_sparql_expression()`.

Added `rasqal_op` enumeration values for built-in aggregate functions `RASQAL_EXPR_GROUP_CONCAT` and `RASQAL_EXPR_SAMPLE` but no expression execution.

Added new bitflags `rasqal_expression_flags` for `rasqal_expression` flags with initial bitflags `RASQAL_EXPR_FLAG_DISTINCT` for distinct (aggregate functions) and `RASQAL_EXPR_FLAG_AGGREGATE` for aggregate functions.

Added `rasqal_new_function_expression2()` for functions with parameters and optional bit flags deprecating `rasqal_new_function_expression()`. This is not capable of adding a user extension aggregate function.

Added new `rasqal_new_aggregate_function_expression()` constructor for making a 1-arg built-in aggregate functions. This is not capable of adding a user extension aggregate function.

The never used `RASQAL_EXPR_GROUP_COND_ASC` and `RASQAL_EXPR_GROUP_COND_DESC` are marked as obsolete.

Updated documentation for `rasqal_expression_visit()`, `rasqal_graph_pattern_visit_fn` and `rasqal_expression_visit_fn` typedef to match what the code actually does.

Added `rasqal_new_group_concat_expression()` for building SPARQL GROUP_CONCAT() expressions with flags, non-empty list of expressions and optional literal separator.

### SPARQL query language changes

Support latest SPARQL 1.1 Query W3C working draft of 1 June 2010 syntax such as:

For SPARQL 1.1 Query, allow `DISTINCT` optionally before extension function expressions with new flag `RASQAL_EXPR_FLAG_DISTINCT`.

Added draft SPARQL 1.1 Query `IF()`, `URI()`, `IRI()`, `STRLANG()`, `STRDT()` and `BNODE()` (with optional expression arg) built-in expressions.

Added draft SPARQL 1.1 Query `IN()` and `NOT IN()` operators.

Adjust draft SPARQL 1.1 Query select expression syntax to latest version: '(' Expr 'AS' Var ')' with required braces.

Added draft SPARQL 1.1 Query aggregate functions `GROUP_CONCAT()` and `SAMPLE()` with new expression enum `RASQAL_EXPR_GROUP_CONCAT` and `RASQAL_EXPR_SAMPLE` as well as formatting to SPARQL and placeholder expression handling implementation - no aggregate expression evaluation. Supports the optional `; SEPARATOR = "string"` syntax for GROUP_CONCAT().

Add support for draft SPARQL 1.1 Query syntax `GROUP BY` a list of select expressions and `HAVING` with a list of expressions.

Add partial support for draft SPARQL 1.1 Query extension (aggregate) functions with DISTINCT and parameters.

Support latest SPARQL 1.1 Update W3C working draft of 1 June 2010 syntax such as:

- `CLEAR GRAPH DEFAULT`
- `CLEAR GRAPH uri`
- `DELETE DATA { ... }`
- `DELETE DATA { GRAPH uri { ... } } INSERT DATA { GRAPH uri { ... } }`
- `DELETE WHERE { ... }`
- `DELETE WHERE { GRAPH uri { ... } }`
- `DELETE { ... } WHERE { ... }`
- `DROP GRAPH uri`
- `DROP SILENT GRAPH uri`
- `INSERT DATA { ... }`
- `INSERT { GRAPH uri { ... } } WHERE { ... }`
- `LOAD uri INTO DEFAULT`
- `LOAD uri INTO uri`
- `LOAD uri`
- `WITH uri DELETE { ... } INSERT { ... } USING NAMED uri WHERE { ... }`

Not all cases may be covered yet since the grammar is hard to implement and may be ambiguous.

### LAQRS syntax support

Start giving deprecated messages for LAQRS `SELECT ... AS varname` (bare variable name) instead of the draft SPARQL 1.1 Query `SELECT ... AS ?varname` with $ or ? symbol.

### Query engine changes

Make query result limit and offset work when no `ORDER BY` is part of the query (yes - this is a well-defined count of under-defined actual results) with the original query engine. Related to Issue#0000352.

Add datatype support for `xsd:date` for value normalization and comparisons.

Handle when results are sorted before used to build triples via `CONSTRUCT`, which has no practical use since triples are not ordered and is less efficient since you have to read all the results into memory. Anyway, it works now.

### Query results formatter class changes

Added an HTML Table results format (name 'table') by Nicholas J Humfrey using patch from Issue#0000360.

A NULL base_uri is valid in `rasqal_query_results_formatter_write()`

### World class changes

Moved generate blank node ID functionality to world class, deprecating the query class methods. Added `rasqal_world_set_default_generate_bnodeid_parameters()`, `rasqal_world_set_generate_bnodeid_handler()` with new handler typedef `rasqal_generate_bnodeid_handler2`.

### Other changes

Made all rasqal destructors simply return when given a `NULL` object pointer. They mostly did this already.

Updated `rasqal.spec.in` based on fedora spec (not tested)

Replace `strncpy()` with `memcpy()` since the the `strncpy()` zero-checking and zero-filling semantics are never needed.

Minimum raptor version is now 1.4.19 so that the `raptor_world` typedef is always available.

## Rasqal 0.9.19 Changes

The only change to this release is to fix the pkg-config `rasqal.pc` file to to restore the dependency on raptor which was accidently deleted. Lesson learnt: do not commit code after midnight local time.

## Rasqal 0.9.18 Changes

The main changes in this release are:

- Add initial draft parsing and API (NOT execution) support for SPARQL 1.1 Update W3C Working Draft of 2010-01-26.
- Add public APIs (row, results, result formatter, variables table) so that query results can be built, read and written without a query.
- Add API resilience checks for invalid NULL pointer arguments.

Fixed Issues:

- 0000320: Add a void* user_data field to rasqal_variable
- 0000323: Official MIME Type for JSON isn't text/json
- 0000343: Mime type for 'table' results format is text/plan
- 0000345: MIME Type and URI for TSV and CSV
- 0000347: rasqal linking fix

### Query API Changes

A user data `void* user_data` field was added to the `rasqal_variable` structure to allow application code to store additional information.

Added a new `rasqal_query_verb` enum value for SPARQL 1.1 (draft) Update: `RASQAL_QUERY_VERB_UPDATE` which indicates that a sequence of update operations are available in the query structure, rather than a query (SELECT, ASK, DESCRIBE).

Added a `rasqal_update_operation` class for holding an updates that adds and/or removes triples from a graph (with possible conditional where) or does a graph administration operation on a grpah.

Added an `rasqal_update_type` enum for the types of graph update - clear, drop, delete, insert and, load.

Added `rasqal_update_type_label()` to get a label for a rasqal-update_type.

      const char* rasqal_update_type_label(rasqal_update_type type);

Added an `rasqal_update_flags` enum for capturing update operations flags such as SPARQL 1.1 Update `SILENT` for silent graph administration operations and `DATA` for bulk insert/delete data, rather than graph pattern templates with variables.

Added `rasqal_query_get_update_operations_sequence()` to get the sequence of updates from a query. Added `rasqal_query_get_update_operation()` get an individual update operation from a query via an index.

      raptor_sequence* rasqal_query_get_update_operations_sequence(rasqal_query* query);

      rasqal_update_operation* rasqal_query_get_update_operation(rasqal_query* query,
        int idx);

### Query Results Class Changes

`rasqal_new_query_results()` added to public API to construct a standalone query result set without being the result of a query execution. (The destructor is already present). Added method `rasqal_query_results_add_row()` to add a row to a query result set.

      rasqal_query_results* rasqal_new_query_results(rasqal_world* world,
         rasqal_query* query, rasqal_query_results_type type,
         rasqal_variables_table* vars_table);

      int rasqal_query_results_add_row(rasqal_query_results* query_results,
         rasqal_row* row);

`rasqal_query_results_type` enum added to public API for use with `rasqal_new_query_results()`.

### Query Results Formatter Class Changes

Registered URIs for the CSV and TSV query result formats and fixed the mime types for those as well as the JSON format as reported in issues Issue #0000345 and Issue #0000323.

Added `rasqal_new_query_results_formatter2()` with format name, mime type and URI args deprecating `rasqal_new_query_results_formatter()` and `rasqal_new_query_results_formatter_by_mime_type()`.

      rasqal_query_results_formatter* rasqal_new_query_results_formatter2(rasqal_world* world,
        const char *name, const char *mime_type, raptor_uri* format_uri);

Added `rasqal_query_results_write2()` and `rasqal_query_results_read2()` with both name and mime_type args deprecating `rasqal_query_results_write()` and `rasqal_query_results_read()` respectively.

      int rasqal_query_results_write2(raptor_iostream *iostr,
        rasqal_query_results *results, const char* name, const char* mime_type,
        raptor_uri *format_uri, raptor_uri *base_uri);

      int rasqal_query_results_read2(raptor_iostream *iostr,
        rasqal_query_results *results, const char* name, const char* mime_type,
        raptor_uri *format_uri, raptor_uri *base_uri);

### Query Result Row Class

Export the query result row class to the public API to allow creating standalone query results set without a query.

Added `rasqal_new_row_for_size()`, `rasqal_free_row()` to construct and destruct a row and `rasqal_row_set_value_at()` to set row literal values.

      rasqal_row* rasqal_new_row_for_size(rasqal_world* world, int size);

      void rasqal_free_row(rasqal_row* row);

      int rasqal_row_set_value_at(rasqal_row* row, int offset,
        rasqal_literal* value);

### Variables Table Class

Added variables table class `rasqal_variables_table` to the public API to allow use in creating a standalone query results.

Added `rasqal_new_variables_table()` and `rasqal_free_variables_table()` to construct and destroy a variables table. Added method `rasqal_variables_table_add()` to add a variable to the variables table.

      rasqal_variables_table* rasqal_new_variables_table(rasqal_world* world);

      void rasqal_free_variables_table(rasqal_variables_table* vt);

      rasqal_variable* rasqal_variables_table_add(rasqal_variables_table* vt,
        rasqal_variable_type type, const unsigned char *name,
        rasqal_literal *value);

### SPARQL Changes

Added syntax-only and API support (no execution) for the SPARQL 1.1 Update W3C Working Draft of 2010-01-26 syntax. These are only available when using the 'laqrs' query language name, until SPARQL 1.1 is stable.

Added new lexer support for keywords: WITH, CLEAR, CREATE, SILENT, DATA, DROP, LOAD

Added `CLEAR` and `CLEAR GRAPH uri`

Added `DROP GRAPH uri`

Added `INSERT DATA { triples }`

Added `DELETE templates` to delete multiple subgraphs.

Added `DELETE DATA { triples }`

Added `LOAD uri` and `LOAD uri INTO graph-uri`

Added `WITH uri DELETE { ... } INSERT { ... } WHERE ...` update form since other combinations are ambiguous.

NOTE: The older LAQRS experimental INSERT and DELETE formats are supported but deprecated.

### Query Engine changes

Nobody reported it, but decimal division was totally broken. Fixed it to do division and not add!

### Other Changes

Multiple code style updates and code file reorganizing.

Link `roqet` directly with `-lraptor` to get raptor symbols used linked directly, to enable alternate library linking approaches to work. Based on the request in Fixes Issue#0000347 and Fedora bug 564885.

Added checks for the public API methods to ensure NULL pointers are not accepted or used.

Added example code for constructing a query result set without a query

Updated `configure` and the build system to use silent rules for the maintainer (by default), or when `--enable-silent-rules` is passed to `configure`. This feature requires building with automake 1.11 which requires autoconf 2.62 or newer when building from GIT.

`autogen.sh` script was updated to enforce the autotools versions above.

The rasqal.pc file now uses the Requires.private field for raptor; it should only be in the link line with
`pkg-config --static ...` is used.

Enforce that only raptor versions <1.9.0 are supported. No Raptor2 or Raptor2 alpha support yet.

## Rasqal 0.9.17 Changes

> WARNING: ABI AND API CHANGED IN THIS RELEASE.

> This means: functions and structs were removed, modified and added.

> Consequently the shared library major soname version has changed from 1 to 2.

The main change in this release is to add a new query engine and to enable it as the default query engine. It supports more of the SPARQL query algebra such as groups and optionals. There were many other changes and fixes.

Fixed Issues: (most of them in query engine 2)

- Issue#0000077: OPTIONAL messes up query results
- Issue#0000128: GROUP graph pattern support in the query engine
- Issue#0000168: Wrong processing of the function "bound" with "OPTIONAL"
- Issue#0000258: Using FILTER with OPTIONAL in SPARQL queries
- Issue#0000261: Some SPARQL queries with multiple OPTIONAL patterns fail to return results
- Issue#0000271: rasqal library does not compile cleanly when using g++ compiler
- Issue#0000279: JSON query binding serializer is returning illegal JSON - extra double quotes before "ordered" and "distinct"
- Issue#0000305: bound gives incoherent results

### Rasqal world API changes

Added methods for setting of an already-opened raptor library to pass into rasqal, rather than it creating one itself. `rasqal_world_open()` can then be called to do the actual initialisation:

      int rasqal_world_open(rasqal_world* world);

      void rasqal_world_set_raptor(rasqal_world* world,
                                   raptor_world* raptor_world_ptr);

      raptor_world *rasqal_world_get_raptor(rasqal_world* world);

Exported new C defines for the library versions: `RASQAL_VERSION` in 6-digit integer MMNNRR format (Major, miNor, Release), `RASQAL_VERSION_STRING` in string "MM.NN.RR" format, `RASQAL_VERSION_MAJOR` for integer major version number, `RASQAL_VERSION_MINOR` for integer minor version number and `RASQAL_VERSION_RELEASE` for integer release number.

API CHANGE: `rasqal_features_enumerate()` gains an initial rasqal_world argument to become a method of the world class:

      int rasqal_features_enumerate(rasqal_world* world,
        const rasqal_feature feature, const char **name,
        raptor_uri **uri, const char **label);

API CHANGE: `rasqal_feature_from_uri()` gains an initial rasqal_world argument to become a method of the world class:

      rasqal_feature rasqal_feature_from_uri(rasqal_world* world,
        raptor_uri *uri);

### Data Graph API changes

API CHANGE: The `rasqal_data_graph` structure gains a new world reference pointer field.

API CHANGE: `rasqal_new_data_graph()` gains an initial rasqal_world argument:

      rasqal_data_graph* rasqal_new_data_graph(rasqal_world* world,
        raptor_uri* uri, raptor_uri* name_uri, int flags);

### Expression API changes

`rasqal_op` enumeration gains values for LAQRS (possible SPARQL 1.1) expression operators: `RASQAL_EXPR_SUM`, `RASQAL_EXPR_AVG`, `RASQAL_EXPR_MIN` and `RASQAL_EXPR_MAX`. It also gains `RASQAL_EXPR_COALESCE` for LAQRS experimental coalesce expression `COALESCE(expression list)`

API CHANGE: The `rasqal_expression` structure gains a new world reference pointer field.

API CHANGE: All `rasqal_expression` constructors gain an initial rasqal_world argument:

      rasqal_expression* rasqal_new_0op_expression(rasqal_world* world,
        rasqal_op op);
      rasqal_expression* rasqal_new_1op_expression(rasqal_world* world,
        rasqal_op op, rasqal_expression* arg);
      rasqal_expression* rasqal_new_2op_expression(rasqal_world* world,
        rasqal_op op, rasqal_expression* arg1, rasqal_expression* arg2);
      rasqal_expression* rasqal_new_3op_expression(rasqal_world* world,
        rasqal_op op, rasqal_expression* arg1,  rasqal_expression* arg2,
        rasqal_expression* arg3);
      rasqal_expression* rasqal_new_string_op_expression(rasqal_world* world,
        rasqal_op op, rasqal_expression* arg1, rasqal_literal* literal);
      rasqal_expression* rasqal_new_literal_expression(rasqal_world* world,
        rasqal_literal* literal);
      rasqal_expression* rasqal_new_function_expression(rasqal_world* world,
        raptor_uri* name, raptor_sequence* args);
      rasqal_expression* rasqal_new_cast_expression(rasqal_world* world,
        raptor_uri* name, rasqal_expression *value);

API CHANGE: `rasqal_expression_evaluate()` gains an initial rasqal_world argument:

      rasqal_literal* rasqal_expression_evaluate2(rasqal_world *world,
        raptor_locator *locator, rasqal_expression* e, int flags);

Added `rasqal_graph_pattern_get_origin()` to get the graph from a GRAPH graph pattern:

      rasqal_literal* rasqal_graph_pattern_get_origin(rasqal_graph_pattern* gp);

Added `rasqal_graph_pattern_set_filter_expression()` and `rasqal_graph_pattern_get_filter_expression()` methods to set/get an expression for a filter graph pattern:

      int rasqal_graph_pattern_set_filter_expression(rasqal_graph_pattern* gp,
        rasqal_expression* expr);

      rasqal_expression*
        rasqal_graph_pattern_get_filter_expression(rasqal_graph_pattern* gp);

### Graph Pattern API changes

`rasqal_graph_pattern_operator` enumeration gains `RASQAL_GRAPH_PATTERN_OPERATOR_FILTER` for a filter graph pattern and `RASQAL_GRAPH_PATTERN_OPERATOR_LET` for LAQRS experimental assignment 'graph pattern'.

API CHANGE: Removed functions `rasqal_graph_pattern_add_constraint()`, `rasqal_graph_pattern_get_constraint_sequence()` and `rasqal_graph_pattern_get_constraint()`. These are replaced by filter graph pattern with expression - functions `rasqal_graph_pattern_set_filter_expression` and `rasqal_graph_pattern_get_filter_expression()`.

### LAQRS Changes

LAQRS is now available in the configuration and does not need to be explicitly selected with `configure`.

Add `SUM()`, `AVG()`, `MIN()` and `MAX()` aggregate expressions to LAQRS. Supported in syntax only, not in any of the query engines.

Add `LET ?var := expression` experimental syntax. Query engine 2 can execute this.

Add `COALESCE(expression list)` experimental expression to return the first defined expression value in the list. Query engines 1 and 2 can execute this.

### Literal API changes

API CHANGE: Reordered `rasqal_literal_type` enumeration to match numeric type promotion order: float is now between integer and double. Also added `RASQAL_LITERAL_XSD_STRING` for xsd:string typed literals and `RASQAL_LITERAL_UDT` for unknown data typed literals. Both were separated out of `RASQAL_LITERAL_STRING` which is now for RDF plain literals and plain/typed turned into RDF terms only

Added `rasqal_literal_get_rdf_term_type()` method to return the RDF term type of a literal as a `rasqal_literal_type` - uri, blank node, literal or cannot be represented (e.g. qname or internal literal types).

      rasqal_literal_type rasqal_literal_get_rdf_term_type(rasqal_literal* l);

Added `rasqal_literal_same_term()` method to perform SPARQL sameTerm() comparison.

      int rasqal_literal_same_term(rasqal_literal* l1, rasqal_literal* l2);

Added `rasqal_literal_is_rdf_literal()` method to check if a literal is an RDF literal (not qname or other internal types).

      int rasqal_literal_is_rdf_literal(rasqal_literal* l);

### Prefix API changes

API CHANGE: The `rasqal_prefix` structure gain a new world reference pointer field.

API CHANGE: `rasqal_new_prefix()` gains an initial rasqal_world argument:

      rasqal_prefix* rasqal_new_prefix(rasqal_world* world,
        const unsigned char* prefix, raptor_uri* uri);

### Query API changes

Added `rasqal_query_dataset_contains_named_graph()` method to check if a named graph is in a dataset:

      int rasqal_query_dataset_contains_named_graph(rasqal_query* query,
                                                    raptor_uri *graph_uri);

### Query Formatter Changes

SPARQL `DESCRIBE` no longer writes commas between terms.

### Query Results API changes

Added `rasqal_query_results_get_query()` method to get the associated query:

      rasqal_query*
        rasqal_query_results_get_query(rasqal_query_results* query_results);

Added `rasqal_graph_pattern_variable_bound_in()` method to check if a graph pattern in a query defines a variable

      int rasqal_graph_pattern_variable_bound_in(rasqal_graph_pattern *gp,
        rasqal_variable *v);

### Query Results Formatter Changes

SPARQL/JSON: Do not emit double " for distinct/ordered flags. Fixes Issue #0000279

Added comma-separated values (CSV), tab-separated values (TSV) and text table output formats with names `csv`, `tsv` and `table`.

### RDQL Changes

Some updates to handle refactored query list of constraint expressions switching to a filter graph pattern. RDQL only has 0 or 1 such expressions in a single query.

### SPARQL Changes

Ensure GroupOrUnionGraphPattern rule constructs the sequence of graph patterns in document order.

OptionalGraphPattern rule is now a list of 1 group graph patterns.

Fix support for `<>` URI literal.

Support `\b`, `\f`, `\'` and `\"` escapes in all types of quoted literals.

Fixed optional `WHERE` in parser to match SPARQL grammar - optional for `DESCRIBE`, but required for `SELECT`, `CONSTRUCT` and `ASK` queries.

### Triples Source API changes

API CHANGE: The `rasqal_triples_source` and `rasqal_triples_source_factory` structures gain API version fields that must be set to a known API version.

API CHANGE: The `rasqal_set_triples_source_factory()` function for registering a triples source factory now take a function with an int error return code, and it returns an int now:

      int rasqal_set_triples_source_factory(rasqal_world* world,
         rasqal_triples_source_factory_register_fn register_fn,
         void* user_data);

### Variable API changes

API CHANGE: The `rasqal_variable` structure gains a variables table pointer.

### Other API changes

`rasqal_triple_parts` adds value `RASQAL_TRIPLE_NONE` for no parts.

`rasqal_compare_flags` enumeration gains `RASQAL_COMPARE_URI` - now also provides RDQL string to bool comparison.

API CHANGE: `rasqal_new_xsd_decimal()` gains an initial rasqal_world argument:

      rasqal_xsd_decimal* rasqal_new_xsd_decimal(rasqal_world* world);

Removed `rasqal_triple_flags` enumeration with unused values: `RASQAL_TRIPLE_FLAGS_EXACT`, `RASQAL_TRIPLE_FLAGS_OPTIONAL` and `RASQAL_TRIPLE_FLAGS_LAST`

### Configure and Build Changes

configure now prefers `pkg-config raptor` to `raptor-config` but will accept both for now. `pkg-config` will not allow compiling against raptor in source tree in future.

Added `--with-query-engine-version` to configure to allow selecting default query engine version - values 1 or 2. This is allowed for people to switch to old engine if necessary for some existing query that the new engine cannot handle. This option will be removed at some point.

Add SHAVE support (`git clone git://git.lespiau.name/shave` ) to "make autotools output sane" which amounts to much less verbose messages when compiling. It is now enabled for the maintainer.

`rasqal-config(1)` is now a wrapper around `pkg-config rasqal`. Consequently `--prefix=DIR` and `--libtool-libs` are ignored.

### Query Engine Changes

An entirely new query execution engine was written. The existing query execution engine was refactored out of a mess of `rasqal_query` and `rasqal_query_results` code and data. It is the default query engine as of Rasqal 0.9.17

The query engine to use can be selected at configure time wiht `--with-query-engine-version` to allow switching to old engine if necessary for some existing query that the new engine cannot handle. This option will be removed at some point.

The interface between the query API and the query engine is now via the `rasqal_rowsource` abstraction - an evaluation of a query returns a rowsource that generates the result rows of variable bindings.

Rewrote `query_results` class to be a pure wrapper around the rowsource and variables table, handling such things like generating triples (CONSTRUCT) from rows, creating a boolean result (ASK) by counting at least 1 result rows and generating syntax results using a query results formatter.

Added a new `rasqal_query_execution_factory` abstraction to provide the interface that the query execution engines implement to return a rowsource to get the results.

Both query engines can potentially be selected at runtime from the query API but ONLY when rasqal is built for development (`configure --enable-maintainer-mode`).

1. If the envariable `RASQAL_DEBUG_ENGINE` is set with value 1 or 2, the query execution engine is chosen.
2. The `roqet(1)` utility gains a `-g` / `--engine` argument.

Query engine 1 (existing):
Existing lazy evaluated engine that is hard to refactor. Internally, implemented by functions named `rasqal_query_engine_1_...()`. Execution factory instance `rasqal_query_engine_1`

Query engine 2 (new):
Based on transforming a tree of SPARQL algebra nodes constructed from the query, into a tree of rowsource-generating expressions that when evaluated at the top, returns the result rows. Each algebra node type and each rowsource type has it's own set of module unit tests built-in. Execution factory instance `rasqal_query_engine_algebra`

Removed query engine core legacy support for `CONSTRUCT *` - never in the SPARQL 1.0 language.

Pulled out row sorting code from query engine 1 into a rasqal_engine_sort module so it can be used by all query engines.

Implemented rowsource abstraction `rasqal_rowsource` for the following types of rowsources:

- empty rowsource: always returns no rows
- filter rowsource: filter an inner rowsource with an expression - used for SPARQL `FILTER`
- graph rowsource: apply a graph variable to an inner rowsource - used for SPARQL `GRAPH` matching
- join rowsource: join two inner rowsources on common variables and an expression. Two types of join supported: left outer join used for SPARQL `OPTIONAL` and natural join for groups of graph patterns.
- project rowsource: pick [project] certain variables from an inner rowsource
- query engine execution rowsource: rows generated by a query execution engine
- row sequence rowsource: built from a sequence of rows
- SPARQL xml rowsource: make rows from SPARQL Results XML syntax
- triples rowsource: create a rowsource by binding variables to an RDF graph sort rowsource: sorts the inner rowsource by an order expression - used for SPARQL `ORDERBY`
- union rowsource: union/concatenation of two inner rowsources - used for SPARQL `UNION`

Renamed row abstraction from `rasqal_query_result_row` to `rasqal_row` since it is independent of query results and shorter.

Use new `rasqal_engine_error` enumeration for query engine/internal errors - OK, FAILED or FINISHED rather than altering `rasqal_query_results` object fields directly.

Documented query execution engine internals as autodocs.

Added a query algebra abstraction `rasqal_algebra` with node type `rasqal_algebra_node_operator` based on SPARQL algebra operators: BGP, FILTER, JOIN, DIFF, LEFTJOIN, UNION, TOLIST, ORDERBY, PROJECT, DISTINCT, REDUCED, SLICE and GRAPH. Some of these are not needed by the query execution engines since they are handled by the high level query API - such as SLICE (limit and offset) and TOLIST (turning results into user data)

Added a variables table abstraction `rasqal_variables_table` pulled out of the internal query results and query structures which now point to it. Constructor `rasqal_new_variables_table()`, destructor `rasqal_free_variables_table()` and methods `rasqal_variables_table_add()`, `rasqal_variables_table_get()`, `rasqal_variables_table_has()`, `rasqal_variables_table_set()`, `rasqal_variables_table_get_value()`, `rasqal_variables_table_get_named_variables_count()`, `rasqal_variables_table_get_anonymous_variables_count()`, `rasqal_variables_table_get_total_variables_count()`, `rasqal_variables_table_get_named_variables_sequence()` and `rasqal_variables_table_get_anonymous_variables_sequence()`.

Allow queries with no graph pattern to be accepted such as SPARQL `DESCRIBE uri` (which the query engine does not execute at present but now is at least parsed).

Do not warn about unbound variables for variables bound in GRAPH and SELECT expressions.

Renamed query language-specific factory class for creating query structure from SPARQL and RDQL syntaxes from `struct rasqal_query_engine_factory` to `rasqal_query_language_factory` since it is about the language, not the engine.

Query engine known problems:

- Variable binding/use scope is not calculated correctly.
- Consequently no queries with `UNION` work correctly.
- Also consequently, some `OPTIONAL` queries execute and return results when they shouldn't due to scoping of variable rules especially in nested optionals.
- `DISTINCT` uses RDF literal equality not RDF sameTerm equality and thus returns results not to spec.
- `xsd:date` comparison is not date-aware, it uses a simple string equality
- `REDUCED` is not implemented.

Summary of the approved DAWG SPARQL 1.0 tests as of Rasqal SVN r15841

    Fail:       22 (4.99 %)
        algebra                        4
        dataset                        3
        distinct                       4
        graph                          2
        open-world                     3
        optional                       4
        reduced                        2
    Pass:      419 (95.01 %)

The above results in EARL: RDF/XML and Turtle

### Internal Changes

Added sparql algebra tests based on the examples in the SPARQL 1.0 Query Language Specification section 12.2.1 Converting Graph Patterns

Optionally support the experimental raptor V2 API.

Lots of resiliency fixes in the case of out of memory - Lauri Aalto.

Adjusted internal test suite to use a perl `improve` script that generates and uses an RDF-based manifest. The test running is now much more consise when successful.

Switch to final DAWG approved testsuite files from http://www.w3.org/2001/sw/DataAccess/tests/r2/ at CVS Revision 1.6 1008

## Rasqal 0.9.16 Changes

> WARNING: ABI AND API CHANGED IN THIS RELEASE.

> This means: functions were removed, modified and added.

> Consequently the shared library major soname version has changed from 0 to 1.

> The header files moved to be installed in PREFIX/include/rasqal such as `/usr/include/rasqal` for usual installs.

> NOTE: In the next release of rasqal, the `rasqal-config` utility that provides the compile and link args will be deprecated, generate a warning when run and will turn into a wrapper for `pkg-config rasqal ...` It will be removed in a future release.

### Major Changes (break ABI and API)

Removed `rasqal_init()` and `rasqal_finish()` functions.

Added a new `rasqal_world` object to manage library allocations and classes with new library constructor/initializing function `rasqal_world *rasqal_new_world(void)` and destructor/cleanup function: `void rasqal_free_world(rasqal_world*)`

The following functions now take a `librdf_world* world` argument as the first argument: `rasqal_language_name_check()`, `rasqal_languages_enumerate()`, `rasqal_new_query()`, `rasqal_query_results_formats_check ()`, `rasqal_new_query_results_formatter()`, `rasqal_new_query_results_formatter_by_mime_type()`, `rasqal_new_integer_literal()`, `rasqal_new_typed_literal()`, `rasqal_new_double_literal()`, `rasqal_new_float_literal()`, `rasqal_new_uri_literal()`, `rasqal_new_pattern_literal()`, `rasqal_new_string_literal()`, `rasqal_new_simple_literal()`, `rasqal_new_boolean_literal()`, `rasqal_new_variable_literal()`, `rasqal_new_decimal_literal()`, `rasqal_new_decimal_literal_from_decimal()`

Removed deprecated `rasqal_new_floating_literal()`, `rasqal_graph_pattern_get_flags()`, `rasqal_expression_foreach()` functions, `RASQAL_LITERAL_FLOATING` macro and `rasqal_expression_foreach_fn` typedef.

Modified `rasqal_triples_match` struct to add a rasqal_world* world field.

There is no more static data such as error pointers, arrays of query languages, URI objects; it is all attached to the rasqal_world object.

### Misc changes

Fixed memory leaks in lang() expression evaluation. (Lauri Aalto)

Made several low-memory resiliance fixes in query construction and execution. (Lauri Aalto)

Library requires raptor 1.4.17 or newer to get the newly public raptor SAX2 API for reading SPARQL XML Results format.

Updated mpfr configure check to look for modern functions rather than functions that are also in the older gmp-mpfr library too.

Only the first error is reported for syntax errors in lex/parse of SPARQL and RDQL since the lack of error recovery means that the consequent messages are of little use.

Fatal errors in SPARQL and RDQL lexer/parser no longer does an abort, but exits via setjmp/longjmp.

### Query Engine Changes

Added internal rowsource class to get rows from an execution engine or a syntax (query result formatter).

### Graph Pattern Class Changes

Modified `rasqal_graph_pattern_add_sub_graph_pattern()` to have an int return value for catching allocation failures.

### Query Class Changes

Modified `rasqal_query_add_variable()` and `rasqal_query_add_prefix()` to have int return values for catching allocation failures.

### Query Results Class Changes

Updated the internals to allow construction of a query result outside the query engine, such as from a syntax.

Added `rasqal_query_results_read()` to read a query results from an iostream in some format.

Modified `rasqal_query_results_formats_enumerate()` to add a flags argument with `RASQAL_QUERY_RESULTS_FORMAT_FLAG_READER` and `RASQAL_QUERY_RESULTS_FORMAT_FLAG_WRITER` choices to choose formats for read or write enumeration.

Removed function `rasqal_query_results_formats_enumerate_full` now handled by `rasqal_query_results_formats_enumerate()`.

Added `rasqal_query_results_formatter_read()` to read query results from a syntax via an iostream.

### Variable Class Changes

Added `rasqal_new_variable_from_variable()` copy constructor.

## Rasqal 0.9.15 Changes

### General Changes

Many updates for better SPARQL support. Rasqal 0.9.15 passes over 92% of the DAWG SPARQL Test Suite as of 2007-11-13.

Rasqal still does not support either `UNION` or `GROUP` and `OPTIONAL` remains buggy. There remain a few other minor areas not yet completely supported such as XSD `date` and XSD `dateTime` equality and comparisons.

> WARNING: ABI AND API CHANGE in Rasqal 0.9.16. The next release of Rasqal will be incompatible with this one.

> It will have both ABI and API changes that will require source updates.

> The shared library major soname will change from 0 to 1.

> The header files will move to be installed in PREFIX/include/rasqal such as `/usr/include/rasqal` for usual installs.

> The full details of the API change have not been decided but the driving change is that using the library will be done via a new Rasqal world object,k will now be used to working like a Redland `librdf_world`. All constructors will take this world object as an argument and all static data will be indirected from the object. Handlers such as the uri_handler/data and error handlers will also move to be set/get via the world object.

> There are almost certainly other API changes and cleanups that will be done, and some possibly some of the data structures may be made internal.

Fixed issues:

- Issue#0000190: Memory leaks in rasqal_literal.c
- Issue#0000191: RAPTOR_API in rasqal.h
- Issue#0000193: SPARQL "ASK" always returns true
- Issue#0000196: Memory leak with RASQAL_REGEX_PCRE
- Issue#0000197: Problem with float comparison in rasqal
- Issue#0000198: rasqal_redland.c compilation errors
- Issue#0000199: SPARQL effective boolean value: empty string literal not false
- Issue#0000200: SPARQL filter scope
- Issue#0000201: SPARQL langMatches patch
- Issue#0000203: API declarations for Symbian portability
- Issue#0000204: SPARQL WHERE is optional
- Issue#0000219: SPARQL BASE makes rasqal query->locator.uri a dangling pointer
- Issue#0000220: Query offset off by one
- Issue#0000221: rasqal_literal_as_integer() with RASQAL_LITERAL_INTEGER literals
- Issue#0000225: SPARQL parser leaks memory on syntax error
- Issue#0000234: autogen.sh $dir quoting
- Issue#0000235: $(EXEEXT) in tests
- Issue#0000236: EOL issues when building svn version on cygwin

### SPARQL Query Language Changes

Many updates to support the SPARQL Candidate Recommendation and Proposed Recommendation versions of the language including:

- Added `REDUCED` syntax support (no query engine support)
- Added `SAMETERM()` support.
- Allowing numbers at the start of local names.
- Allowing `@`lang and `^^`datatype after triple-quoted literals.
- Make unary + and - work
- Remove `CONSTRUCT *` that is no longer in the spec
- Removed hexadecimal literals which were never in the spec
- Made queries with the `ASK` verb work again.
- Made `LANG()` and `DATATYPE()` work to spec on typed literals.
- Remove warning about optional SPARQL `WHERE` although it is still a dumb idea to have useless keywords.

### Query Engine Changes

Many internal changes were made including refactoring the engine core and adding of additional internal documentation for the engine functions.

Substantial improvements were made to datatypes support:

- SPARQL / XQuery / XPath numeric type promotion is now supported, including derived types of `xsd:integer` etc.
- Added XSD `xsd:decimal` implementation either using GNU MP, MPFR, C99 `_Decimal` (but I have yet to find a working implementation) or by default and inaccurately, C doubles.
- Added XSD `xsd:dateTime` initial support for validation.
- Numeric operations such as +, -, *, / and ! as well as comparisons are now done in the appropriate datatype (which may be a promotion).

Improved the way that literal equality and comparisons work especially with respect to datatypes. Triple pattern matching (equality) works with RDF terms. SPARQL `FILTER` literal equality and comparisons follow SPARQL rules with possible numeric type promotion, then using RDF Term if the types are different. `ORDER` comparison or `DISTINCT` equality checks use RDF Term. RDQL execution uses it's own existing "stringy" rules.

Set the query base URI.

Make queries that bind the origin (SPARQL `GRAPH`) match correctly against the default graph.

Memory reduction in stack usage when evaluation expressions (such as SPARQL `FILTER`s).

### Public API changes

Added `rasqal_home_url_string` static constant.

Added `rasqal_xsd_decimal` class and API calls described below.

Added a `decimal` part to the rasqal_literal union value for `RASQAL_LITERAL_DECIMAL` types.

Added a `parent_type` part to the rasqal_literal when the type can be promoted.

Added `RASQAL_EXPR_SAMETERM` expression

Added `RASQAL_COMPARE_RDF` and `RASQAL_COMPARE_URI` comparison types for RDF Term comparsion rules and allowing URI comparison (without `STR()`) respectively.

Added `rasqal_new_typed_literal()` to make an RDF typed literal from a type and string (no language).

Added `rasqal_new_float_literal()` for wrapping a C `float` as XSD float.

Added new decimal literal constructor rasqal_literal* rasqal_new_decimal_literal_from_decimal(const unsigned char *string, rasqal_ xsd_decimal* decimal)

Added `rasqal_literal_datatype` method to get the datatype URI of a literal.

Added `rasqal_literal_value` method to get the literal value of a literal, looking up any variables to their value. FIXME should this not involve query results?

Added addition `rasqal_triple_parts` enums: `RASQAL_TRIPLE_GRAPH` for just the named graph part `RASQAL_TRIPLE_SPO` for subject, predicate and objects and `RASQAL_TRIPLE_SPOG` for all parts including named grpah.

### Decimal Class

A new `rasqal_xsd_decimal` class was added to handle XSD decimals with accurate decimal arithmetic.

Constructor:

    rasqal_xsd_decimal* rasqal_new_xsd_decimal(void);

Destructor:

    void rasqal_free_xsd_decimal(rasqal_xsd_decimal* dec);

Methods:

    double rasqal_xsd_decimal_get_double(rasqal_xsd_decimal* dec);
    int rasqal_xsd_decimal_set_double(rasqal_xsd_decimal* dec, double d);
    iint rasqal_xsd_decimal_set_string(rasqal_xsd_decimal* dec, const char* string);
    int rasqal_xsd_decimal_set_long(rasqal_xsd_decimal* dec, long l);
    int rasqal_xsd_decimal_print(rasqal_xsd_decimal* dec, FILE* stream);
    char* rasqal_xsd_decimal_as_string(rasqal_xsd_decimal* dec);
    char* rasqal_xsd_decimal_as_counted_string(rasqal_xsd_decimal* dec, size_t* len_p);

Numeric methods (writing to the `result` argument):

    int rasqal_xsd_decimal_add(rasqal_xsd_decimal* result,
                               rasqal_xsd_decimal* a, rasqal_xsd_decimal* b);
    int rasqal_xsd_decimal_subtract(rasqal_xsd_decimal* result,
                                    rasqal_xsd_decimal* a, rasqal_xsd_decimal* b);
    int rasqal_xsd_decimal_multiply(rasqal_xsd_decimal* result,
                                    rasqal_xsd_decimal* a, rasqal_xsd_decimal* b);
    int rasqal_xsd_decimal_divide(rasqal_xsd_decimal* result,
                                  rasqal_xsd_decimal* a, rasqal_xsd_decimal* b);
    int rasqal_xsd_decimal_negate(rasqal_xsd_decimal* result,
                                  rasqal_xsd_decimal* a);

Comparison methods:

    int rasqal_xsd_decimal_compare(rasqal_xsd_decimal* a, rasqal_xsd_decimal* b);
    int rasqal_xsd_decimal_equals(rasqal_xsd_decimal* a, rasqal_xsd_decimal* b);
    int rasqal_xsd_decimal_is_zero(rasqal_xsd_decimal* d);

### Query Results Formatter Class Changes

Updated to the 4th version of the SPARQL XML Results format by removing the `ordered` and `distict` attributes. Removed support for all the earlier versions 1 to 3.

### `roqet` Utility Changes

Added `-D` / `--data` options for specifying data URis for the default graph and `-G` / `--named` for URIs of named graphs (the existing `-s` is a also a synonym for the latter).

### Other Changes

Many internal fixes and cleanups after failures so that memory is not lost and/or rasqal does not crash. These many changes were primarily made by Lauri Aalto.

Several portability fixes for helping with low-memory, embedded systems and using a compiler that is not gcc.

The SPARQL test runner `check-sparql` was improved to read the SPARQL XML Results format (but not via `XML::Simple` because it is insanely complex and counterintuitive), handle DAWG test manifests and generate EARL reports. It also has new help and usage messages.

## Rasqal 0.9.14 Changes

### General Changes

Added syntax and API support (but no query engine support) for experimental extensions to SPARQL called LAQRS: LAQRS Adds to Querying RDF in SPARQL.

Updated the query results formatter to allow better introspection of supported formats.

Fixed issues:

- Issue#0000152: Allow `<_:NAME>` to work as `_:NAME` in SPARQL.
- Issue#0000156: Add LAQRS extensions to SPARQL grammar
- Issue#0000160: rasqal_strcasecmp without prototype
- Issue#0000167: Make CONSTRUCT work with LIMIT
- Issue#0000182: Allow '-' in SPARQL language tags (and RDQL)

### LAQRS Adds to Querying RDF in SPARQL (LAQRS)

LAQRS is experimental and Rasqal provides only syntax and API support (but no query engine support) for:

- `DELETE` via query verb `RASQAL_QUERY_VERB_DELETE`
- `EXPLAIN` as a keyword allowed before any query. Returned by `rasqal_query_get_explain()`
- `INSERT` via query verb `RASQAL_QUERY_VERB_INSERT`
- `COUNT()` and COUNT(*) via new expressions `RASQAL_EXPR_COUNT` and `RASQAL_EXPR_VARSTAR`
- `SELECT` expression `AS` variable via the new expression field of rasqal_variable
- `GROUP BY` results via rasqal_query_get_group_conditions_sequence() and rasqal_query_get_group_condition() and new expressions `RASQAL_EXPR_GROUP_COND_ASC` and `RASQAL_EXPR_GROUP_COND_DESC`

Repeating THERE IS NO QUERY ENGINE SUPPORT FOR ANY OF THE ABOVE

LAQRS is not enabled by default in Rasqal (unless using maintainer mode or building from Subversion). To enable it, configure Rasqal like this:

    $ ./configure '--enable-query-languages=sparql rdql laqrs'
    ...

    Rasqal build summary:
      RDF query languages available : rdql sparql
      RDF query languages enabled   : sparql rdql laqrs
      Triples source                : raptor 1.4.15
    $

The API changes for LAQRS are as follows:

Added new query verbs `RASQAL_QUERY_VERB_DELETE` and `RASQAL_QUERY_VERB_INSERT`

Added a constructor to create a constant or 0-operand expression (for COUNT):

    rasqal_expression* rasqal_new_0op_expression(rasqal_op op);

Added a query method to get the explain flag:

    int rasqal_query_get_explain(rasqal_query* query);

Added a query method to get the 'group by' condition expressions:

    raptor_sequence*
    rasqal_query_get_group_conditions_sequence(rasqal_query* query);

    rasqal_expression*
    rasqal_query_get_group_condition(rasqal_query* query, int idx);

Added `rasqal_expression` expression types:

- `RASQAL_EXPR_GROUP_COND_ASC` for group condition ascending.
- `RASQAL_EXPR_GROUP_COND_DESC` for group condition descending.
- `RASQAL_EXPR_COUNT` for select `COUNT()`
- `RASQAL_EXPR_VARSTAR` for select `COUNT(*)`

`rasqal_variable` now has a `rasqal_expression*` field `expression`.

### Configuration and Build Changes

The pkgconfig rasqal.pc file and the `rasqal-config` script now separates directly linked shared libraries and indirectly linked ones. This prevents unnecessary references to libraries. The regular libraries includes -L plus `-lrasqal` and the dynamic and static libraries are available with:

- `pkgconfig rasqal --static --libs`
- `rasqal-config --libs --private-libs`

So for example to statically link with rasqal, use either:

    $ cc .. -o foo foo.c `pkgconfig rasqal --static --libs`

    $ cc .. -o foo foo.c `rasqal-config --libs --private-libs`

### Query Results Formatter Changes

Made it easier to discover and create of query results in a syntax by using a MIME Type.

Added query results formatter constructor by required mime type:

    rasqal_query_results_formatter*
    rasqal_new_query_results_formatter_by_mime_type(const char *mime_type);

Added a method to return the mime type of a selected formatter:

    const char*
    rasqal_query_results_formatter_get_mime_type(
      rasqal_query_results_formatter *formatter);

Added another query results formatter static method to enumerate possible results formats, their names, labels and (new) mime type.

    int
    rasqal_query_results_formats_enumerate_full(const unsigned int counter,
      const char **name, const char **label,
      const unsigned char **uri_string, const char **mime_type);

Added a static method to check for support for a query results format.

    int rasqal_query_results_formats_check(const char *name,
      raptor_uri* uri, const char *mime_type);

### SPARQL Query Language Changes

Updated for the SPARQL Query Language for RDF, W3C Working Draft 26 March 2007

- Added `REDUCED` token. This entailed changing the distinct flag from a boolean to a mode. `rasqal_query_get_distinct` and `rasqal_query_set_distinct` now takes a mode (0, 1 DISTINCT, 2 REDUCED) rather than the former boolean flag. There is no query engine support for REDUCED at present.

### Query Engine Changes

Added the possibility that a query's native result is a syntax (rather than natively bindings, boolean or triples) and added a method to check for that:

    int rasqal_query_results_is_syntax(rasqal_query_results* query_results);

Many query engine internal changes, but these remain unsupported: OPTIONAL graph pattern (partially working), GROUP graph pattern (no support), UNION graph pattern (no support) and new `SELECT REDUCED` (no support).

### `roqet` Utility Changes

`roqet` can use -r to generate a chosen result syntax for bindings results or triples (using raptor).

roqet now generates namespace declarations for triples when serializing output. The result is that they are used when the serializer handles them such as generating RDF/XML (Abbreviated) or Turtle.

### Other Changes

`rasqal_expression` lost the unused `rasqal_variable*` field `variable`

Added exported variables to return the license string in `rasqal_license_string` and home page in `rasqal_home_url_string`

## Rasqal 0.9.13 Changes

### General Changes

Added a new `rasqal_query_results_formatter` class.

Many internal query engine changes, mostly to separate query and query_results internals so that eventually the run-time execution context is entirely separated from the static query structure.

Added query features system with one initial feature `RASQAL_FEATURE_NO_NET`.

### Configuration and Build Changes

Allow shell variable `LEX` to be set to things that aren't exactly `flex` Recommend flex 2.5.33 and update configure to point at the main flex site whichq finally gets 2.5.33 after 9 years.

`PKGCONFIG` vars not substituted correctly in configure.ac. Remove @LDFLAGS from rasqal.pc.in. Fixes Issue#0000098.

Win32 build fixes.Correct win32 static linking of rasqal. (Fixes Issue#0000100) and include float.h and `#define isnan` on win32. (Fixes Issue#0000111).

In maintainer mode, add all the supported compiler `-W` warning flags to the CFLAGS.

Declare several rasqal functions with GCC printf-formatting attributes when using a new enough GCC.

Remove broken debug messages. #0000131.

### SPARQL Query Language Changes

Added labels to grammar tokens using bison to give better error messages.

Fix looking for EOF in an unsigned variable since it may be negative on some systems.

The query engine now implements SPARQL `GRAPH` matching.

### RDQL Query Language Changes

Added labels to grammar tokens using bison to give better error messages.

Fix looking for EOF in an unsigned variable since it may be negative on some systems.

### Query Engine Changes

The query engine now implements SPARQL `GRAPH` matching.

Merge only all adjacent sequences of basic graph pattern triples, not anything with triples such as optional BGP triples. Fixes Issue#0000080.

When an exact triple match is present, do not execute a query forever. Fixes Issue#0000094.

Fail if a variable argument to `LANG()` has an undefined value rather than try to execute a NULL pointer. Fixes Issue#0000113.

Add query / query_results link early so reference counting is done right. Fixes Issue#0000095.

Report failure as well as query finished when an error occurs during making results. Fixes Issue#0000118.

Added a hack to check an outer constraint expression. Fixes Issue#0000129.

Free origins (`GRAPH` nodes) in triples to prevent memory leak. Fixes Issue#0000133.

### Query API Changes

Added a new `rasqal_query_results_formatter` class to format `librdf_query_results` into a syntax. Also added a `rasqal_query_results_formats_enumerate()` function to enumerate all the supported formats. The query results method `rasqal_query_results_write()` was changed to use this class internally.

Added a new feature system to allow setting parameters on the query parser/engine. Initially have one feature `RASQAL_FEATURE_NO_NET` that prevents network requests during a query execution. Added functions: `rasqal_features_enumerate`, `rasqal_get_feature_count`, `rasqal_feature_from_uri`, `rasqal_feature_value_type`, `rasqal_query_set_feature`, `rasqal_query_set_feature_string`, `rasqal_query_get_feature`, `rasqal_query_get_feature_string`.

`roqet` gained a `-f` / `--feature` option to set query features.

## Rasqal 0.9.12 Changes

### General Changes

Added JSON as a query results format based on the Serializing SPARQL Query Results in JSON draft.

Added query writing to a `raptor_iostream` which allows reading in one query language and writing in another. The only useful consequence of this now is that it enables `roqet` to become an RDQL to SPARQL translator.

Rasqal now requires raptor 1.4.9 or newer.

### Configuration and Build Changes

Now using subversion.

### `roqet` utility Changes

Altered the `-d` (`--dump-query`) option to now take an argument of the query format to dump. The values it can take are `debug`, `structure` or `sparql`.

To convert a query from RDQL to SPARQL, use:

    roqet -q -i rdql -d sparql -n query.rdql > query.sparql

Added `-r json` for JSON query results output based on the draft defined in the Serializing SPARQL Query Results in JSON draft

### SPARQL Query Language Changes

Updated to match SPARQL Query Language for RDF, W3C Candidate Recommendation 6 April 2006. All DAWG syntax tests now pass. The update includes near alignment with SPARQL grammar term names except where the flex/bison approach diverged.

Updated SPARQL tests from DAWG CVS

Finally removed long deprecated `ASC[]` and `DESC[]` syntax.

### RDQL Query Language Changes

Handle empty regex `//` Fixes Issue#0000071

### Query Engine Changes

Some updates to handle latest changes to SPARQL grammar.

Added `RASQAL_EXPR_REGEX` 3-arg operation to match the SPARQL `regex()` 2/3-arg function.

Many internal changes to move more of the query execution state from inside `rasqal_query` to inside `rasqal_query_results` and related structures. This is not yet complete but when done, you will be able to execute the same query more than once at the same time.

### Query API Changes

Added `rasqal_query_write` to write a query structure into a syntax onto a raptor_iostream. Implements writing SPARQL format with format URI NULL, http://www.w3.org/TR/rdf-sparql-query/ or http://www.w3.org/TR/2006/CR-rdf-sparql-query-20060406/

Added a JSON SPARQL query results format with format URI identifier http://www.w3.org/2001/sw/DataAccess/json-sparql/ based on the draft defined in http://www.w3.org/2001/sw/DataAccess/json-sparql/ Implemented document with version `alt-ser-sparql.rst,v 1.3 2006/02/16 16:03:08 k Exp`.

`rasqal_query_get_all_variable_sequence` was corrected to match the definition - return all variables, not just the bound (`SELECT`ed) ones. Fixes Issue#00000079.

Added `rasqal_query_get_anonymous_variable_sequence` to return only anonymous variables after change above.

Added `rasqal_graph_pattern_get_index` to get the absolute index of a graph pattern in a graph.

### IOstream class Changes

Added `rasqal_query_iostream_write_escaped_counted_string` and `rasqal_query_escape_counted_string` to format an escaped string suitable for using inside a query.

### Documentation Changes

Updated `roqet.1` for --exec option and new usages.

## Rasqal 0.9.11 Changes

### General Changes

Duplicated `SELECT` variables are now detected, give a warning and are removed.

Rasqal now requires raptor 1.4.8 or newer to get the guess parser that uses URI/name and mime type returned from protocol request (if available) to choose the correct parser.

Added an internal `rasqal_map` key : value map for use with result duplicate detection and ordering.

A major source code regoranisation moved all library source code to the `src/` dir, roqet to `utils/` and other documentation to `docs/`. This should only affect packagers, not any functionality.

Many more function documentation were added to the sources for use by gtk-doc.

### SPARQL Query Language Changes

Updated to the SPARQL Query Language for RDF W3C Working Draft 23 November 2005:

- Added `isIRI` keywords.
- Updated the name definitions to allow initial _ in variable names.
- Changed the decimal and double literal syntax.
- Allow negative numeric literals.
- Change the AND and OR logic when an error is present.

Added a post 2005-11-23 SPARQL WD syntax change: added `langMatches` operator and initial query engine support.

Invalid `\u` HHHH and `\U` HHHHHHHH hex escapes and floating point number formats are detected and warned.

Updates to the query engine make `DISTINCT` and `ORDER BY` now work, including with `LIMIT`.

The lexer now counts line numbers correctly over multi-line comments.

Updated changes to the valid characters allowed in SPARQL names for variable, prefix and QNames.

### RDQL Query Language Changes

The lexer now counts line numbers correctly over multi-line comments.

### Query Engine Changes

When query result sorting is used with limit (SPARQL `LIMIT`) and offset, they now work correctly, performing the limit and offset after ordering the result. This matches the SPARQL query result semantics.

The query engine now implements distinct results (SPARQL `DISTINCT`) including with ordering (SPARQL `ORDER BY`).

More cases with optional graph patterns (SPARQL `OPTIONAL`s) are now executed correctly. Note: this does not mean all cases work, there are known problems with executing optional clauses.

Added types for `xsd:float` (C float) and `xsd:double` (C double); `xsd:decimal` (handled as a string) and `xsd:datetime` (as a string).

Fixed (a compare b) between integers and doubles to be the right sign.

Do not promote literals early on in comparisons to strings "perl style" but do the best type-based comparsion as late as possible.

### Query API Changes

Added `rasqal_new_double_literal`.

Added `rasqal_graph_pattern_visit` and type for visitor function `rasqal_graph_pattern_visit_fn`.

Added `rasqal_new_expression_from_expression`.

Added `rasqal_expression_visit` and type for visitor function `rasqal_expression_visit_fn`.

Deprecated function `rasqal_new_floating_literal` replaced by new `rasqal_new_double_literal`.

Deprecated function `rasqal_expression_foreach`, replaced by new `rasqal_expression_visit`.

Function `rasqal_expression_evaluate` gains a flag argument of new enum `rasqal_compare_flags`.

Added enum `rasqal_compare_flags` flags for `rasqal_expression_evaluate` or `rasqal_literal_compare`. Type `RASQAL_COMPARE_XQUERY` can be used with to ask for use of XQuery comparison and type promotions.

Added `rasqal_literal` types: `RASQAL_LITERAL_DECIMAL`, `RASQAL_LITERAL_DATETIME`, `RASQAL_LITERAL_DOUBLE` (replacing deprecated `RASQAL_LITERAL_FLOATING`) and `RASQAL_LITERAL_FLOAT`. Reordered the `rasqal_literal` types in the enum.

The enum types in `rasqal_literal_type` were reordered to make them match sparql type promotion.

### `roqet` utility program changes

`roqet` gains -e/--exec option to execute a query string directly rather than via a file or URI containing the query.

Now writes out XML results format in format with version URI `http://www.w3.org/2005/06/sparqlResults` and short name "xml". The previous version is available with short name "xml-v2". The latest version now writes `ordered` and `distinct` boolean-valued attributes on the `results` element.

### Configuration Changes

The autogen.sh script for building from CVS was revamped to be more modular.

`configure` now takes an `--enable-gtk-doc` option to enable building of the documentation using the `gtk-doc` utility. It is by default enabled only if the utility is available.

### Documentation Changes

The GNOME `gtk-doc` program is now used to automatically extract documentation from source comments into reference documentation. This is then merged with templates and additional documentation to provide a reference manual for rasqal as XML document which is turned into HTML along with GNOME devhelp support.

This new documentation intended to replace the librasqal manual page/web page as easier to read document with scope for better expanding with more detail of rasqal including examples and tutorial information. The librasqal manual page will continue to contain the summary information for the present.

## Rasqal 0.9.10 Changes

### General Changes

The query engine now supports ordering query results, in SPARQL this is the `ORDER BY` clause.

### SPARQL Query Language Changes

The SPARQL parser now passes (accepts) all the 70+ SyntaxFull tests in the RDF Data Access Working Group (DAWG) test suite for SPARQL. This mostly means accepting optional punctuation in some places.

Sorting results with `ORDER BY` now partially works however comparison is not done with the SPARQL literal comparison rules (after XQuery) but using the existing RDQL-style "string-y" comparisons.

Allow `<>` as a URI.

The SPARQL parser now accepts some changes made by the DAWG after the last published working draft: SPARQL Query Language for RDF, W3C Working Draft, 19 April 2005. This includes:

- In `ORDER BY` `ASC(`expression`)` replaces `ASC[...]`, `DESC(`expression`)` replaces `DESC[...]`, and it also accepts `ORDER BY (`expression`)`. `ORDER BY` func()`` is accepted although at present no extension function support is available that could use it.
- `[]` can be used in the triple predicate position as an anonymous existential variable
- Enforce that ASK queries cannot use `ORDER BY`, `LIMIT` or `OFFSET`

Omitting `WHERE` gives a warning. Don't do that!

### Query Engine Changes

The query engine now allows sorting of results (`ORDER BY` in SPARQL). It performs comparisons using the existing RDQL style and does not yet support the SPARQL literal comparison rules. Sorting can be done by a sequence of expressions, ascending or descending. If the final result is equality, the object pointers are used.

Note: removal of duplicates is not supported yet.

Some test code for datatypes support was added, not enabled by default and not yet useful.

### Query API Changes

Removed functions deprecated in 0.9.9.

Added `rasqal_graph_pattern_operator` enumeration with values for the main SPARQL graph patterns, graph pattern class method `rasqal_graph_pattern_get_operator` and graph pattern utility function `rasqal_graph_pattern_operator_as_string`

Modified the type of the final argument of `rasqal_new_graph_pattern_from_sequence` and `rasqal_graph_pattern_add_triples` from an integer to a `rasqal_graph_pattern_operator` enumeration.

Deprecated function `rasqal_graph_pattern_get_flags` now always returning 0 replaced by the graph pattern operator functions listed above .

### `roqet` utility program changes

Removed deprecated flags -f and -o

## Rasqal 0.9.9 Changes

### General Changes

SPARQL is now the default query language

Added a signing memory debugging system to aid checking when rasqal-allocated memory is freed in another library or vice-versa enabled by `--with-memory-signing` configure option (defaults to on in maintainer mode).

Fixed a few internal malloc/frees to use RASQAL_MALLOC / RASQAL_FREE so that the above signed memory system worked.

### SPARQL Query Language Changes

Grammar updated to follow the SPARQL Query Language for RDF, W3C Working Draft, 19 April 2005. This changes many parts of the syntax:

- Turtle/N3 style for triples with abbreviations
- `{` ... `}` around triple patterns
- `OPTIONAL` instead of `[]`
- `GRAPH` replaces `SOURCE`
- `FROM NAMED` replaces `LOAD`
- `FILTER` replaces `AND`
- `REGEX` replaces `?var =~ /match/flags` and `!~`
- Added `LIMIT`, `OFFSET` and `ORDER BY` with `ASC[]` and `DESC[]`
- Changed function syntax to remove `&`
- Removed old operator tokens: `ne`, `eq`, `==`

(Note: the query engine does not support sorting amongst other recently added SPARQL features)

SPARQL keywords are now case independent rather than just upper or lowercase.

Added """long literals""" after N3 (and soon, Turtle) and '''long literals''' for SPARQL only.

Added many SPARQL tests from DAWG most not yet approved by the working group. Not all pass either because not implemented or known bugs.

Added the revised SPARQL Query Results XML Format (the latest version not yet published) support to `rasqal_query_results_write` when called with format URI `http://www.w3.org/2001/sw/DataAccess/rf1/result2`.

### Query Engine Changes

Uses the query results limit and offset information to skip initial results (offset) and provide a maximum number of results (limit).

Moved some engine-specific operations from RDQL and SPARQL parser.

Added internal `rasqal_formula` class for the Turtle part of the SPARQL parser

Deprecated the `rasqal_triples_source` factory method `new_triples_match`. It is replaced by a new method `init_triples_match` and will be removed from the next release.

### Query API Changes

Added bnode identifier generation functions: `rasqal_query_set_default_generate_bnodeid_parameters`, `rasqal_query_set_generate_bnodeid_handler` based on the raptor API for generating blank node identifiers in the Turtle/N3 triple style.

Added `order_conditions_sequence` to the query structure to store query ordering conditions and added access methods `rasqal_query_get_order_conditions_sequence` and `rasqal_query_get_order_condition` to read the resulting expressions.

Added expressions for SPARQL ordering conditions: `RASQAL_EXPR_ORDER_COND_ASC`, `RASQAL_EXPR_ORDER_COND_DESC` and `RASQAL_EXPR_ORDER_COND_NONE`.

Added types for variables in two version - normal and anonymous with an new enum `rasqal_variable_type` and `rasqal_new_variable_typed` to allow creating them.

Completed the distinct/limit and offset get/set methods by adding: `rasqal_query_set_distinct`, `rasqal_query_set_limit`, `rasqal_query_get_offset` and `rasqal_query_set_offset`

Deprecated the `rasqal_triple` flags field - the value `RASQAL_TRIPLE_FLAGS_EXACT` was only used in internals of the execution engine. The value `RASQAL_TRIPLE_FLAGS_OPTIONAL` was never used. Optionals are now noted on graph patterns. Deprecated `rasqal_triple_set_flags` and `rasqal_triple_get_flags`.

Added enum `rasqal_query_verb` for the main query verbs: `RASQAL_QUERY_VERB_SELECT` `RASQAL_QUERY_VERB_CONSTRUCT` `RASQAL_QUERY_VERB_DESCRIBE` and `RASQAL_QUERY_VERB_ASK`. Added method `rasqal_query_get_verb` to access the verb.

Added `rasqal_query_get_query_graph_pattern` to get the top graph pattern.

Added `rasqal_query_get_wildcard` to get the query verb wildcard flag such as with SPARQL `SELECT *`

Added `rasqal_query_get_construct_triples_sequence` and `rasqal_query_get_construct_triple` to get the triples made from a SPARQL `CONSTRUCT` query.

### `roqet` utility program changes

Updated roqet to include better query structure walking with `-w` / `--walk` including listing query verb, distinct, limit, offset flags, construct triples and easier to read groupings of graph patterns and triples.

Deprecated roqet arguments `-f` / `--format` and `-o` / `--output` in place of `-r` / `--results` as both choose the query results format.

SPARQL is now the default query language for roqet.

## Rasqal 0.9.8 Changes

### SPARQL Query Language Changes

Grammar updated to follow the SPARQL Query Language for RDF, W3C Working Draft, 17 February 2005.

Added support for casting in constraint expresions for datatyped literals with the syntax qname`(`literal`)` such as `xsd:decimal("10")`.

Added named graphs parsing with `LOAD` and note that `UNION` cannot be handled yet, `SOURCE` and `[`...`]` syntax for optionals are deprecated.

### Query Engine Changes

Engine now operates over a hierarchy of `rasqal_graph_pattern` objects, where at the root the query has a single query graph rather than a sequence of graph patterns. The query graph contains the former sequence of graph patterns.

Constraints can be applied to any graph pattern, not just at the top level of a query.

Added casting expressions type `RASQAL_EXPR_CAST` and constructor `rasqal_new_cast_expression`.

Fixed setting of a triple origin (SPARQL `GRAPH`) which was not working in 0.9.7

`xsd:boolean` RDF literals are now promoted into internal `RASQAL_LITERAL_BOOLEAN` typed `rasqal_literal` like for XSD integer and double.

The query engine uses the named graph information when evaluating queries, passing it to the `rasqal_triples_match` factory methods either implemented with raptor or redland as a `rasqal_triples_source_factory` and returning them as results of variable bindings.

### Query API Changes

Added no-arg constructor `rasqal_new_graph_pattern`

Added method `rasqal_graph_pattern_add_triples` to add triples to an existing graph pattern.

Added methods `rasqal_graph_pattern_add_constraint`, `rasqal_graph_pattern_get_constraint_sequence` and `rasqal_graph_pattern_get_constraint` to add constraints to a graph pattern.

Added method `rasqal_graph_pattern_add_sub_graph_pattern` to add a sub-graph pattern to a graph pattern.

Added a Data Graph class with constructor `rasqal_new_data_graph`, destructor `rasqal_free_data_graph` and debug method `rasqal_data_graph_print`.

Added query methods for data graphs: `rasqal_query_add_data_graph`, `rasqal_query_get_data_graph_sequence`, `rasqal_query_get_data_graph`.

Deprecated query methods `rasqal_query_add_constraint`, `rasqal_query_get_constraint_sequence` `rasqal_query_get_constraint`, `rasqal_query_add_source`, `rasqal_query_get_source_sequence` and `rasqal_query_get_source`. These will be removed in the next release.

Removed functions deprecated in previous version: `rasqal_query_get_variable_sequence` and `rasqal_query_add_triple`.

## Rasqal 0.9.7 Changes

### General Changes

Fix a resource clean up when query results are either not read at all or not fully exhausted. This caused a problem in Redland when it held on to MySQL database handles despite a query having ended.

Added option `-n/--dryrun` to `roqet` to stop after preparing the query. Added option `-w/--walk-query` to walk and print the query using the graph API.

New build configuration and portability fixes for win32 (John Barstow)

Portability fixes for win32 - define `RASQAL_INLINE` and use it as for raptor. (Dave Viner)

Make rasqal tests work when building against raptor in a sibling source tree.

### Query Engine Changes

Added a graph pattern API with `rasqal_graph_pattern` typedef and `rasqal_pattern_flags` enum with value `RASQAL_PATTERN_FLAGS_OPTIONAL` to allow complete walking of the query structure.

Two new methods to the query class were added to support this: `rasqal_query_get_graph_pattern_sequence` to get the raptor_sequence of graph patterns in a query and `rasqal_query_get_graph_pattern` to get individual an graph pattern by index.

The new graph pattern methods added are:

- `rasqal_graph_pattern_get_triple` to get a `raptor_triple` inside a graph pattern.
- `rasqal_graph_pattern_get_sub_graph_pattern_sequence` to get the raptor_sequence of sub-graph patterns.
- `rasqal_graph_pattern_get_sub_graph_pattern` to get a sub-graph pattern inside a graph pattern by index.
- `rasqal_graph_pattern_get_flags` to get a graph pattern's flags.
- `rasqal_graph_pattern_print` to print a graph pattern in a debug form.

Deprecated `rasqal_query_add_triple` as it doesn't construct the graph patterns and is of little use as it does not build the correct query structures.

Added query API methods to get the bound and all variables in a query: `rasqal_query_get_bound_variable_sequence` and `rasqal_query_get_all_variable_sequence` respectively. Deprecated `rasqal_query_get_variable_sequence` as too ambiguous.

With the aid of gcc `-Wswitch-enum`, found and fixed cases where switch on enumerated values were missing cases. The remaining cases return failure or an error message rather than abort(). This fixed a crash when comparing for equality a variable ?x with a blank node value and an interger.

Deleted `RASQAL_EXPR_PATTERN` as it was never used.

Added `rasqal_query_get_distinct` to get a query-specified distinct results flag.

Added `rasqal_query_get_limit` to get a query-specified limit on the number of results.

### SPARQL Query Language Changes

Updated some of the SPARQL syntax to match the changes in the SPARQL Query Language for RDF W3C Working Draft of 17 February 2005. Added `GRAPH` replacing `SOURCE` and `WITH` replacing `FROM`. Added warnings about using the older forms and about using `[`...`]` instead of `OPTIONAL`.

Added recording of `DISTINCT` and `LIMIT` in the query structures but not yet used by the query engine.

### RDQL Query Language Changes

None.

## Rasqal 0.9.6 Changes

### General Changes

Fix a bug in writing a query result to XML when blank nodes are used. Now also correctly uses the base URI when pass in to the writing method.

Added support for three types of query result - bindings (the only one in previous versions), an RDF graph and a boolean. Added `rasqal_query_results` methods to test the type of the result: `rasqal_query_results_is_bindings`, `rasqal_query_results_is_boolean` and `rasqal_query_results_is_graph`.

Added `rasqal_query_results_get_triple` to get current triple as a `raptor_statement` and `rasqal_query_results_next_triple` to move to the next triple.

Added `rasqal_query_results_get_boolean` to get a boolean query result value.

Added `rasqal_triple` copy constructor `rasqal_new_triple_from_triple`.

### Query Engine Changes

Constructs an RDF graph result as a sequence of triples. This enables the SPARQL `CONSTRUCT` form to work.

Can return a boolean result indicating that there were variable binding results, but not returning them. This enables the SPARQL `ASK` form to work.

Added a new function expression - rasqal_op enum value `RASQAL_EXPR_FUNCTION`, added new `name` and `args` fields to the `rasqal_expression` structure and added `rasqal_new_function_expression` to construct this expression.

Added new 1-argument expression `RASQAL_EXPR_STR` returning a string version of the expression.

Added new 1-argument expressions operating on RDF literals: `RASQAL_EXPR_LANG` returning the language string of an RDF literal, `RASQAL_EXPR_DATATYPE` returning the datatype URI of an RDF literal.

Added new 1-argument testing expressions returning booleans: `RASQAL_EXPR_BOUND` true if the variable argument is bound to a value, `RASQAL_EXPR_ISURI` true if the argument is a URI, `RASQAL_EXPR_ISBLANK` true if the argument is a blank node and `RASQAL_EXPR_ISLITERAL` true if the argument is an RDF literal.

Fixed a problem in optional results returning extra results with no new bindings.

### SPARQL Query Language Changes

The SPARQL Parser now allows UTF-8 and \u, \U in prefixes and QNames.

Now supports `CONSTRUCT` and `ASK` queries using the updated query engine features.

`OPTIONAL` can now be used wherever `[` ... `]` could be used (parser bug fix).

Now supports the SPARQL built-in functions `STR()` returning a string version of the expression, `LANG()` returning the language string of an RDF literal, `DATATYPE()` returning the datatype URI of an RDF literal, `BOUND()` testing if a variable is bound, `ISURI()` testing if an expression is a URI, `ISBLANK()` testing if an expression is a blank node and `ISLITERAL()` testing if an expression is an RDF literal.

Now supports SPARQL `BASE` directive for setting the base URI of a query. This is experimental and may not be in the next version or may not be in the final SPARQL language.

The parser now expands QNames correctly when used in literals like `"blah"^^xsd:string`.

### RDQL Query Language Changes

The RDQL Parser now allows UTF-8 and \u, \U in prefixes and QNames. This makes RDQL testsuite tests S-03, S-04 and S-05 work.

## Rasqal 0.9.5 Changes

A release with major changes internal to the query engine to operate over graph patterns instead of sequences of triple patterns and to add execution of optional graph patterns. Additionally the query results can now be written in a recognised XML format.

This version of Rasqal requires Raptor 1.4.4.

### Core Changes

Added a `rasqal_graph_pattern` class for handling matching a graph pattern (set of triple patterns) in an `rasqal_query`. RDQL only has one of these wheras SPARQL may have many, and they may be nested (this may change, as SPARQL is under development).

Added `rasqal_query_results_write` method to write variable binding query results to a `raptor_iostream` in the XML format defined by SPARQL Variable Binding Results XML Format, W3C Working Draft, 21 December 2004.

### Query Engine Changes

Updated the query engine to operate over graph patterns rather than a single sequence of triple patterns. The graph patterns may be optional, which is used to implement SPARQL optionals. Nested graph patterns are constructed but cannot yet be executed.

Added a unary minus expression type.

Improved the type promotion for expression evaluation. Try to evaluate strings as doubles or integers if the operation contains one double or integer respectively.

Fixed a memory leak with string matches/non-matches.

### SPARQL Query Language Changes

Optional graph patterns `OPTIONAL` and `[` ... `]` now work.

Added the `{` ... `}` group syntax and removed the `(` ... `)` form.

`$` was added as an allowed variable prefixes.

A warning was added to show `SOURCE *` is ignored.

Added the `UNION` keyword, unsupported.

Rasqal now passes the DAWG SPARQL test cases: Optional triples (dawg-opt-query-001, dawg-opt-query-002, dawg-opt-query-003, dawg-opt-query-004) and examples from query WD (sparql-query-example-2.1a, sparql-query-example-2.2a, sparql-query-example-2.3a, sparql-query-example-2.4a, sparql-query-example-3)

Allow UTF-8 qname prefixes and check name against XML name constraints.

Recover lexer state from errors in regexes.

Terminate the lexer on a syntax error, rather than produce multiple errors.

### RDQL Query Language Changes

The lexer now handles UTF-8 qname prefixes, enabling RDQL testsuite test S-02 to pass.

Allow UTF-8 qname prefixes and check name against XML name constraints.

Recover lexer state from errors in regexes.

Terminate the lexer on a syntax error, rather than produce multiple errors.

## Rasqal 0.9.4 Changes

Pass on raptor parser errors to rasqal's error routines and upwards.

Clean up several memory allocations when a query fails to prepare or execute fully.

Fixed lexer jams when a query contained an illegal variable name after a '?'.

Fixed lexer crashes when a query ended in a regex pattern like `/abc/`.

Tidied up the testing framework so 'make distcheck' works.

## Rasqal 0.9.3 Changes

Rasqal's License was changed from LGPL 2.1/MPL 1.1 to LGPL 2.1/Apache 2

Added support for the SPARQL Query Language for RDF, W3C Working Draft, 12 October 2004 from the W3C RDF Data Access Working Group (DAWG). The support is at the basic syntax level - token lexer and grammar parser which passes the first simple tests from the proposed DAWG testcases. No additional query engine support has been added for SPARQL features that are not supported by RDQL.

Queries can now be prepared and then executed multiple times.

Added configure `--enable-query-languages` option with `rdql` and `sparql` as the choices.

Thanks to Chris Pointon for several patches to make Rasqal easier to build under Win32. Applied with some modifications. Renamed the RDQL and SPARQL syntax tokens ERROR to ERROR_TOKEN to help.

Added experimental support for querying multiple sources; the same query is executed over each source in turn. Also added some support for returning the source URI which is not yet enabled as this feature is in flux in the DAWG work. This may change or be removed in future versions.

`roqet` can specify a data source URI on the command line with `-s` / `--source`) URI for queries executing against an implicit model.

Added the DAWG SPARQL test cases driven from the manifest.n3 format. Created tests from the examples in the working draft.

Added an experimental XML result format for bindings, based on DAWG work. Enabled in `roqet` with `-o xml`. This is very likely to change or replaced in future versions.

Added `roqet` argument `-d` / `--dump-query` to dump the processed query, rather than do it by default (0.9.2 and earlier).

`roqet` can now read queries from URIs, using the `raptor_www` class to do the retrieval.

Fixed the `configure` checks for a posix regex function regcomp to correctly discover it is present.

### Internal changes

Added support for declaring prefixes for XML-style QNames both before and after their use.

The struct `rasqal_prefix` gained a `declared` field.

The struct `rasqal_triple` gained an origin field; not used at present but intended to support work on tracking triple provenance such as provided by Redland Contexts.

Added methods `rasqal_triple_set_origin` and `rasqal_triple_get_origin` to support the above.

struct `rasqal_triple_meta` now takes a 4-array of bindings, the fourth being the origin.

Exported function `rasqal_set_triples_source_factory` publically as originally intended.

## Rasqal 0.9.2 Changes

This release made minor portability fixes for building with C++ and Win32 (untested).

Several functions changed their parameters or return values from char* to unsigned char* or const unsigned char* to reflect the actual use.

Changed to return a `const unsigned char*`:
`rasqal_literal_as_string`

Changed to take `const unsigned char*` (or add `const`):
`rasqal_new_floating_literal`
`rasqal_new_pattern_literal`
`rasqal_new_prefix`
`rasqal_new_simple_literal`
`rasqal_new_string_literal`
`rasqal_new_variable`
`rasqal_query_has_variable`
`rasqal_query_results_get_binding_name`
`rasqal_query_results_get_binding_value_by_name`
`rasqal_query_results_get_bindings`
`rasqal_query_set_variable`

## Rasqal 0.9.1 Changes

This release changed the way that results were returned. A new `rasqal_query_results` class was created. This allows for a clean separation of the two concepts allowing multiple form of the results to be retrieved as methods of the query_results class, rather than the query class. The only form of results currently available is variable bindings, but RDF graphs will be returned in future, as a set of triples in a serialised form.

The execution method `rasqal_query_execute` was changed to return a new object of that class rather than an `int` success or failure.

The following methods of the `rasqal_query` class were renamed and moved to the new `rasqal_query_results` class:

0.9.0 name | 0.9.1+ name
--- | ---
`rasqal_query_get_result_count` | `rasqal_query_results_get_count`
`rasqal_query_next_result` | `rasqal_query_results_next`
`rasqal_query_results_finished` | `rasqal_query_results_finished`
`rasqal_query_get_result_bindings` | `rasqal_query_results_get_bindings`
`rasqal_query_get_result_binding_value` | `rasqal_query_results_get_binding_value`
`rasqal_query_get_result_binding_name` | `rasqal_query_results_get_binding_name`
`rasqal_query_get_result_binding_by_name` | `rasqal_query_results_get_binding_value_by_name`
`rasqal_query_get_bindings_count` | `rasqal_query_results_get_bindings_count`

A new `rasqal_free_query_results` destructor was created to delete the query results. (There is no public constructor).

Other minor bugs were fixed such as multiple constraints now being ANDed and not ORed, and adding defensive code for when queries fail and results methods are invoked.

## Rasqal 0.9.0 Changes

It is all new.

Copyright (C) 2004-2014 Dave Beckett
Copyright (C) 2003-2005 University of Bristol