SQL Compliance

Contents

• SQL Compliance

  • Mandatory Features

  • Optional Features

  • See Also

vsql aims to be SQL compliant by following the 2016 SQL Standard in both BNF syntax and mandatory features.

There are still many features to be implemented before it can be considered fully compliant - as shown by the Mandatory Features table below.

Mandatory Features

As of the latest version (or at least the version of this documentation) vsql supports 62 of the 164 mandatory features of the SQL:2016 Standard.

Table 43 — Feature taxonomy and definition for mandatory features

Feature ID	Feature Name
✅ E011	Numeric data types
✅ E011-01	INTEGER and SMALLINT data types (including all spellings)
✅ E011-02	REAL, DOUBLE PRECISON, and FLOAT data types
✅ E011-03	DECIMAL and NUMERIC data types
✅ E011-04	Arithmetic operators
✅ E011-05	Numeric comparison
✅ E011-06	Implicit casting among the numeric data types
⭕ E021	Character string types
✅ E021-01	CHARACTER data type (including all its spellings)
✅ E021-02	CHARACTER VARYING data type (including all its spellings)
✅ E021-03	Character literals
✅ E021-04	CHARACTER_LENGTH function
✅ E021-05	OCTET_LENGTH function
✅ E021-06	SUBSTRING function
✅ E021-07	Character concatenation
✅ E021-08	UPPER and LOWER functions
✅ E021-09	TRIM function
❌ E021-10	Implicit casting among the fixed-length and variable-length character string types
✅ E021-11	POSITION function
⭕ E021-12	Character comparison
✅ E031	Identifiers
✅ E031-01	Delimited identifiers
✅ E031-02	Lower case identifiers
✅ E031-03	Trailing underscore
⭕ E051	Basic query specification
❌ E051-01	SELECT DISTINCT
✅ E051-02	GROUP BY clause
✅ E051-04	GROUP BY can contain columns not in <select list>
✅ E051-05	Select list items can be renamed
❌ E051-06	HAVING clause
✅ E051-07	Qualified * in select list
❌ E051-08	Correlation names in the FROM clause
✅ E051-09	Rename columns in the FROM clause
⭕ E061	Basic predicates and search conditions
✅ E061-01	Comparison predicate
✅ E061-02	BETWEEN predicate
❌ E061-03	IN predicate with list of values
✅ E061-04	LIKE predicate
❌ E061-05	LIKE predicate: ESCAPE clause
✅ E061-06	NULL predicate
❌ E061-07	Quantified comparison predicate
❌ E061-08	EXISTS predicate
❌ E061-09	Subqueries in comparison predicate
❌ E061-11	Subqueries in IN predicate
❌ E061-12	Subqueries in quantified comparison predicate
❌ E061-13	Correlated subqueries
✅ E061-14	Search condition
❌ E071	Basic query expressions
❌ E071-01	UNION DISTINCT table operator
❌ E071-02	UNION ALL table operator
❌ E071-03	EXCEPT DISTINCT table operator
❌ E071-05	Columns combined via table operators need not have exactly the same data type.
❌ E071-06	Table operators in subqueries
❌ E081	Basic Privileges
❌ E081-01	SELECT privilege at the table level
❌ E081-02	DELETE privilege
❌ E081-03	INSERT privilege at the table level
❌ E081-04	UPDATE privilege at the table level
❌ E081-05	UPDATE privilege at the column level
❌ E081-06	REFERENCES privilege at the table level
❌ E081-07	REFERENCES privilege at the column level
❌ E081-08	WITH GRANT OPTION
❌ E081-09	USAGE privilege
❌ E081-10	EXECUTE privilege
⭕ E091	Set functions
✅ E091-01	AVG
✅ E091-02	COUNT
✅ E091-03	MAX
✅ E091-04	MIN
✅ E091-05	SUM
❌ E091-06	ALL quantifier
❌ E091-07	DISTINCT quantifier
✅ E101	Basic data manipulation
✅ E101-01	INSERT statement
✅ E101-03	Searched UPDATE statement
✅ E101-04	Searched DELETE statement
❌ E111	Single row SELECT statement
❌ E121	Basic cursor support
❌ E121-01	DECLARE CURSOR
❌ E121-02	ORDER BY columns need not be in select list
❌ E121-03	Value expressions in ORDER BY clause
❌ E121-04	OPEN statement
❌ E121-06	Positioned UPDATE statement
❌ E121-07	Positioned DELETE statement
❌ E121-08	CLOSE statement
❌ E121-10	FETCH statement: implicit NEXT
❌ E121-17	WITH HOLD cursors
✅ E131	Null value support (nulls in lieu of values)
⭕ E141	Basic integrity constraints
❌ E141-01	NOT NULL constraints
❌ E141-02	UNIQUE constraints of NOT NULL columns
✅ E141-03	PRIMARY KEY constraints
❌ E141-04	Basic FOREIGN KEY constraint with the NO ACTION default for both referential delete action and referential update action
❌ E141-06	CHECK constraints
❌ E141-07	Column defaults
❌ E141-08	NOT NULL inferred on PRIMARY KEY
❌ E141-10	Names in a foreign key can be specified in any order
✅ E151	Transaction support
✅ E151-01	COMMIT statement
✅ E151-02	ROLLBACK statement
❌ E152	Basic SET TRANSACTION statement
❌ E152-01	SET TRANSACTION statement: ISOLATION LEVEL SERIALIZABLE clause
❌ E152-02	SET TRANSACTION statement: READ ONLY and READ WRITE clauses
❌ E153	Updatable queries with subqueries
❌ E161	SQL comments using leading double minus
⭕ E171	SQLSTATE support
❌ E182	Host language binding
⭕ F031	Basic schema manipulation
✅ F031-01	CREATE TABLE statement to create persistent base tables
❌ F031-02	CREATE VIEW statement
❌ F031-03	GRANT statement
❌ F031-04	ALTER TABLE statement: ADD COLUMN clause
❌ F031-13	DROP TABLE statement: RESTRICT clause
❌ F031-16	DROP VIEW statement: RESTRICT clause
❌ F031-19	REVOKE statement: RESTRICT clause
⭕ F041	Basic joined table
✅ F041-01	Inner join (but not necessarily the INNER keyword)
✅ F041-02	INNER keyword
✅ F041-03	LEFT OUTER JOIN
✅ F041-04	RIGHT OUTER JOIN
❌ F041-05	Outer joins can be nested
❌ F041-07	The inner table in a left or right outer join can also be used in an inner join
✅ F041-08	All comparison operators are supported (rather than just =)
⭕ F051	Basic date and time
✅ F051-01	DATE data type (including support of DATE literal)
✅ F051-02	TIME data type (including support of TIME literal) with fractional seconds precision of at least 0.
✅ F051-03	TIMESTAMP data type (including support of TIMESTAMP literal) with fractional seconds precision of at least 0 and 6.
❌ F051-04	Comparison predicate on DATE, TIME, and TIMESTAMP data types
❌ F051-05	Explicit CAST between date-time types and character string types
✅ F051-06	CURRENT_DATE
✅ F051-07	LOCALTIME
✅ F051-08	LOCALTIMESTAMP
❌ F081	UNION and EXCEPT in views
❌ F131	Grouped operations
❌ F131-01	WHERE, GROUP BY, and HAVING clauses supported in queries with grouped views
❌ F131-02	Multiple tables supported in queries with grouped views
❌ F131-03	Set functions supported in queries with grouped views
❌ F131-04	Subqueries with GROUP BY and HAVING clauses and grouped views
❌ F131-05	Single row SELECT with GROUP BY and HAVING clauses and grouped views
❌ F181	Multiple module support
✅ F201	CAST function
❌ F221	Explicit defaults
❌ F261	CASE expression
❌ F261-01	Simple CASE
❌ F261-02	Searched CASE
✅ F261-03	NULLIF
✅ F261-04	COALESCE
⭕ F311	Schema definition statement
✅ F311-01	CREATE SCHEMA
✅ F311-02	CREATE TABLE for persistent base tables
❌ F311-03	CREATE VIEW
❌ F311-04	CREATE VIEW: WITH CHECK OPTION
❌ F311-05	GRANT statement
❌ F471	Scalar subquery values
❌ F481	Expanded NULL predicate
❌ F812	Basic flagging
❌ S011	Distinct data types
❌ T321	Basic SQL-invoked routines
❌ T321-01	User-defined functions with no overloading
❌ T321-02	User-defined stored procedures with no overloading
❌ T321-03	Function invocation
❌ T321-04	CALL statement
❌ T321-05	RETURN statement
❌ T631	IN predicate with one list element

Optional Features

Table 44 — Feature taxonomy for optional features

Feature ID	Feature Name
❌ B011 1	Embedded Ada
❌ B012 1	Embedded C
❌ B013 1	Embedded COBOL
❌ B014 1	Embedded Fortran
❌ B015 1	Embedded MUMPS
❌ B016 1	Embedded Pascal
❌ B017 1	Embedded PL/I
❌ B021	Direct SQL
❌ B031	Basic dynamic SQL
❌ B032	Extended dynamic SQL
❌ B032-01	<describe input statement>
❌ B033	Untyped SQL-invoked function arguments
❌ B034	Dynamic specification of cursor attributes
❌ B035	Non-extended descriptor names
❌ B041	Extensions to embedded SQL exception declarations
❌ B051	Enhanced execution rights
❌ B111 1	Module language Ada
❌ B112 1	Module language C
❌ B113 1	Module language COBOL
❌ B114 1	Module language Fortran
❌ B115 1	Module language MUMPS
❌ B116 1	Module language Pascal
❌ B117 1	Module language PL/I
❌ B121	Routine language Ada
❌ B122	Routine language C
❌ B123	Routine language COBOL
❌ B124	Routine language Fortran
❌ B125	Routine language MUMPS
❌ B126	Routine language Pascal
❌ B127	Routine language PL/I
❌ B128	Routine language SQL
❌ B200	Polymorphic table functions
❌ B201	More than one PTF generic table parameter
❌ B202	PTF Copartitioning
❌ B203	More than one copartition specification
❌ B204	PRUNE WHEN EMPTY
❌ B205	Pass-through columns
❌ B206	PTF descriptor parameters
❌ B207	Cross products of partitionings
❌ B208	PTF component procedure interface
❌ B209	PTF extended names
❌ B211	Module language Ada: VARCHAR and NUMERIC support
❌ B221	Routine language Ada: VARCHAR and NUMERIC support
❌ F032	CASCADE drop behavior
❌ F033	ALTER TABLE statement: DROP COLUMN clause
❌ F034	Extended REVOKE statement
❌ F034-01	REVOKE statement performed by other than the owner of a schema object
❌ F034-02	REVOKE statement: GRANT OPTION FOR clause
❌ F034-03	REVOKE statement to revoke a privilege that the grantee has WITH GRANT OPTION
❌ F052	Intervals and datetime arithmetic
❌ F053	OVERLAPS predicate
❌ F054	TIMESTAMP in DATE type precedence list
❌ F111	Isolation levels other than SERIALIZABLE
❌ F111-01	READ UNCOMMITTED isolation level
❌ F111-02	READ COMMITTED isolation level
❌ F111-03	REPEATABLE READ isolation level
❌ F121	Basic diagnostics management
❌ F121-01	GET DIAGNOSTICS statement
❌ F121-02	SET TRANSACTION statement: DIAGNOSTICS SIZE clause
❌ F122	Enhanced diagnostics management
❌ F123	All diagnostics
❌ F171	Multiple schemas per user
❌ F191	Referential delete actions
❌ F200	TRUNCATE TABLE statement
❌ F202	TRUNCATE TABLE: identity column restart option
❌ F222	INSERT statement: DEFAULT VALUES clause
❌ F251	Domain support
❌ F262	Extended CASE expression
❌ F263	Comma-separated predicates in simple CASE expression
❌ F271	Compound character literals
❌ F281	LIKE enhancements
❌ F291	UNIQUE predicate
❌ F301	CORRESPONDING in query expressions
❌ F302	INTERSECT table operator
❌ F302-01	INTERSECT DISTINCT table operator
❌ F302-02	INTERSECT ALL table operator
❌ F304	EXCEPT ALL table operator
❌ F312	MERGE statement
❌ F313	Enhanced MERGE statement
❌ F314	MERGE statement with DELETE branch
❌ F321	User authorization
❌ F361	Subprogram support
❌ F381	Extended schema manipulation
❌ F381-01	ALTER TABLE statement: ALTER COLUMN clause
❌ F381-02	ALTER TABLE statement: ADD CONSTRAINT clause
❌ F381-03	ALTER TABLE statement: DROP CONSTRAINT clause
❌ F382	Alter column data type
❌ F383	Set column not null clause
❌ F384	Drop identity property clause
❌ F385	Drop column generation expression clause
❌ F386	Set identity column generation clause
❌ F391	Long identifiers
❌ F392	Unicode escapes in identifiers
❌ F393	Unicode escapes in literals
❌ F394	Optional normal form specification
❌ F401	Extended joined table
❌ F401-01	NATURAL JOIN
❌ F401-02	FULL OUTER JOIN
❌ F401-04	CROSS JOIN
❌ F402	Named column joins for LOBs, arrays, and multisets
❌ F403	Partitioned join tables
❌ F404	Range variable for common column names
❌ F411	Time zone specification
❌ F421	National character
❌ F431	Read-only scrollable cursors
❌ F431-01	FETCH with explicit NEXT
❌ F431-02	FETCH FIRST
❌ F431-03	FETCH LAST
❌ F431-04	FETCH PRIOR
❌ F431-05	FETCH ABSOLUTE
❌ F431-06	FETCH RELATIVE
❌ F441	Extended set function support
❌ F442	Mixed column references in set functions
❌ F451	Character set definition
❌ F461	Named character sets
❌ F491	Constraint management
❌ F492	Optional table constraint enforcement
❌ F521	Assertions
❌ F531	Temporary tables
❌ F555	Enhanced seconds precision
❌ F561	Full value expressions
✅ F571	Truth value tests
❌ F591	Derived tables
❌ F611	Indicator data types
❌ F641	Row and table constructors
✅ F651	Catalog name qualifiers
❌ F661	Simple tables
❌ F671	Subqueries in CHECK constraints
❌ F672	Retrospective check constraints
❌ F673	Reads SQL-data routine invocations in CHECK constraints
❌ F690	Collation support
❌ F692	Enhanced collation support
❌ F693	SQL-session and client module collations
❌ F695	Translation support
❌ F701	Referential update actions
❌ F711	ALTER domain
❌ F721	Deferrable constraints
❌ F731	INSERT column privileges
❌ F741	Referential MATCH types
❌ F751	View CHECK enhancements
❌ F761	Session management
✅ F762	CURRENT_CATALOG
✅ F763	CURRENT_SCHEMA
❌ F771	Connection management
❌ F781	Self-referencing operations
❌ F791	Insensitive cursors
❌ F801	Full set function
❌ F813	Extended flagging
❌ F821	Local table references
❌ F831	Full cursor update
❌ F831-01	Updateable scrollable cursors
❌ F831-02	Updateable ordered cursors
❌ F841	LIKE_REGEX predicate
❌ F842	OCCURRENCES_REGEX function
❌ F843	POSITION_REGEX function
❌ F844	SUBSTRING_REGEX
❌ F845	TRANSLATE_REGEX
❌ F846	Octet support in regular expression operators
❌ F847	Nonconstant regular expressions
❌ F850	Top-level <order by clause> in <query expression>
❌ F851	<order by clause> in subqueries
❌ F852	Top-level <order by clause> in views
❌ F855	Nested <order by clause> in <query expression>
❌ F856	Nested <fetch first clause> in <query expression>
❌ F857	Top-level <fetch first clause> in <query expression>
❌ F858	<fetch first clause> in subqueries
❌ F859	Top-level <fetch first clause> in views
❌ F860	dynamic <fetch first row count> in <fetch first clause>
❌ F861	Top-level <result offset clause> in <query expression>
❌ F862	<result offset clause> in subqueries
❌ F863	Nested <result offset clause> in <query expression>
❌ F864	Top-level <result offset clause> in views
❌ F865	dynamic <offset row count> in <result offset clause>
❌ F866	FETCH FIRST clause: PERCENT option
❌ F867	FETCH FIRST clause: WITH TIES option
❌ R010	Row pattern recognition: FROM clause
❌ R020	Row pattern recognition: WINDOW clause
❌ R030	Row pattern recognition: full aggregate support
❌ S023	Basic structured types
❌ S024	Enhanced structured types
❌ S025	Final structured types
❌ S026	Self-referencing structured types
❌ S027	Create method by specific method name
❌ S028	Permutable UDT options list
❌ S041	Basic reference types
❌ S043	Enhanced reference types
❌ S051	Create table of type
❌ S071	SQL paths in function and type name resolution
❌ S081	Subtables
❌ S091	Basic array support
❌ S091-01	Arrays of built-in data types
❌ S091-02	Arrays of distinct types
❌ S091-03	Array expressions
❌ S092	Arrays of user-defined types
❌ S094	Arrays of reference types
❌ S095	Array constructors by query
❌ S096	Optional array bounds
❌ S097	Array element assignment
❌ S098	ARRAY_AGG
❌ S111	ONLY in query expressions
❌ S151	Type predicate
❌ S161	Subtype treatment
❌ S162	Subtype treatment for references
❌ S201	SQL-invoked routines on arrays
❌ S201-01	Array parameters
❌ S201-02	Array as result type of functions
❌ S202	SQL-invoked routines on multisets
❌ S211	User-defined cast functions
❌ S231	Structured type locators
❌ S232	Array locators
❌ S233	Multiset locators
❌ S241	Transform functions
❌ S242	Alter transform statement
❌ S251	User-defined orderings
❌ S261	Specific type method
❌ S271	Basic multiset support
❌ S272	Multisets of user-defined types
❌ S274	Multisets of reference types
❌ S275	Advanced multiset support
❌ S281	Nested collection types
❌ S291	Unique constraint on entire row
❌ S301	Enhanced UNNEST
❌ S401	Distinct types based on array types
❌ S402	Distinct types based on multiset types
❌ S403	ARRAY_MAX_CARDINALITY
❌ S404	TRIM_ARRAY
❌ T021	BINARY and VARBINARY data types
❌ T022	Advanced support for BINARY and VARBINARY data types
❌ T023	Compound binary literals
❌ T024	Spaces in binary literals
✅ T031	BOOLEAN data type
❌ T041	Basic LOB data type support
❌ T041-01	BLOB data type
❌ T041-02	CLOB data type
❌ T041-03	POSITION, LENGTH, LOWER, TRIM, UPPER, and SUBSTRING functions for LOB data types
❌ T041-04	Concatenation of LOB data types
❌ T041-05	LOB locator: non-holdable
❌ T042	Extended LOB data type support
❌ T043	Multiplier T
❌ T044	Multiplier P
❌ T051	Row types
❌ T053	Explicit aliases for all-fields reference
❌ T061	UCS support
❌ T071	BIGINT data type
❌ T076	DECFLOAT data type
❌ T101	Enhanced nullability determination
❌ T111	Updatable joins, unions, and columns
❌ T121	WITH (excluding RECURSIVE) in query expression
❌ T122	WITH (excluding RECURSIVE) in subquery
❌ T131	Recursive query
❌ T132	Recursive query in subquery
❌ T141	SIMILAR predicate
❌ T151	DISTINCT predicate
❌ T152	DISTINCT predicate with negation
❌ T171	LIKE clause in table definition
❌ T172	AS subquery clause in table definition
❌ T173	Extended LIKE clause in table definition
❌ T174	Identity columns
❌ T175	Generated columns
✅ T176	Sequence generator support
✅ T177	Sequence generator support: simple restart option
❌ T178	Identity columns: simple restart option
❌ T180	System-versioned tables
❌ T181	Application-time period tables
❌ T191	Referential action RESTRICT
❌ T201	Comparable data types for referential constraints
❌ T211	Basic trigger capability
❌ T211-01	Triggers activated on UPDATE, INSERT, or DELETE of one base table.
❌ T211-02	BEFORE triggers
❌ T211-03	AFTER triggers
❌ T211-04	FOR EACH ROW triggers
❌ T211-05	Ability to specify a search condition that shall be True before the trigger is invoked.
❌ T211-06	Support for run-time rules for the interaction of triggers and constraints.
❌ T211-07	TRIGGER privilege
❌ T211-08	Multiple triggers for the same event are executed in the order in which they were created in the catalog.
❌ T212	Enhanced trigger capability
❌ T213	INSTEAD OF triggers
❌ T231	Sensitive cursors
❌ T241	START TRANSACTION statement
❌ T251	SET TRANSACTION statement: LOCAL option
❌ T261	Chained transactions
❌ T271	Savepoints
❌ T272	Enhanced savepoint management
❌ T281	SELECT privilege with column granularity
❌ T285	Enhanced derived column names
❌ T301	Functional dependencies
❌ T312	OVERLAY function
❌ T323	Explicit security for external routines
❌ T324	Explicit security for SQL routines
❌ T325	Qualified SQL parameter references
❌ T326	Table functions
❌ T331	Basic roles
❌ T332	Extended roles
❌ T341	Overloading of SQL-invoked functions and SQL-invoked procedures
❌ T351	Bracketed comments
❌ T431	Extended grouping capabilities
❌ T432	Nested and concatenated GROUPING SETS
❌ T433	Multiargument GROUPING function
❌ T434	GROUP BY DISINCT
❌ T441	ABS and MOD functions
❌ T461	Symmetric BETWEEN predicate
❌ T471	Result sets return value
❌ T472	DESCRIBE CURSOR
❌ T491	LATERAL derived table
❌ T495	Combined data change and retrieval
❌ T501	Enhanced EXISTS predicate
❌ T502	Period predicates
❌ T511	Transaction counts
❌ T521	Named arguments in CALL statement
❌ T522	Default values for IN parameters of SQL-invoked procedures
❌ T523	Default values for INOUT parameters of SQL-invoked procedures
❌ T524	Named arguments in routine invocations other than a CALL statement
❌ T525	Default values for parameters of SQL-invoked functions
❌ T551	Optional key words for default syntax
❌ T561	Holdable locators
❌ T571	Array-returning external SQL-invoked functions
❌ T572	Multiset-returning external SQL-invoked functions
❌ T581	Regular expression substring function
❌ T591	UNIQUE constraints of possibly null columns
❌ T601	Local cursor references
❌ T611	Elementary OLAP operations
❌ T612	Advanced OLAP operations
❌ T613	Sampling
❌ T614	NTILE function
❌ T615	LEAD and LAG functions
❌ T616	Null treatment option for LEAD and LAG functions
❌ T617	FIRST_VALUE and LAST_VALUE functions
❌ T618	NTH_VALUE function
❌ T619	Nested window functions
❌ T620	WINDOW clause: GROUPS option
❌ T621	Enhanced numeric functions
❌ T622	Trigonometric functions
❌ T623	General logarithm functions
❌ T624	Common logarithm functions
❌ T625	LISTAGG
❌ T641	Multiple column assignment
❌ T651	SQL-schema statements in SQL routines
❌ T652	SQL-dynamic statements in SQL routines
❌ T653	SQL-schema statements in external routines
❌ T654	SQL-dynamic statements in external routines
❌ T655	Cyclically dependent routines
❌ T811	Basic SQL/JSON constructor functions
❌ T812	SQL/JSON: JSON_OBJECTAGG
❌ T813	SQL/JSON: JSON_ARRAYAGG with ORDER BY
❌ T814	Colon in JSON_OBJECT or JSON_OBJECTAGG
❌ T821	Basic SQL/JSON query operators
❌ T822	SQL/JSON: IS JSON WITH UNIQUE KEYS predicate
❌ T823	SQL/JSON: PASSING clause
❌ T824	JSON_TABLE: specific PLAN clause
❌ T825	SQL/JSON: ON EMPTY and ON ERROR clauses
❌ T826	General value expression in ON ERROR or ON EMPTY clauses
❌ T827	JSON_TABLE: sibling NESTED COLUMNS clauses
❌ T828	JSON_QUERY
❌ T829	JSON_QUERY: array wrapper options
❌ T830	Enforcing unique keys in SQL/JSON constructor functions
❌ T831	SQL/JSON path language: strict mode
❌ T832	SQL/JSON path language: item method
❌ T833	SQL/JSON path language: multiple subscripts
❌ T834	SQL/JSON path language: wildcard member accessor
❌ T835	SQL/JSON path language: filter expressions
❌ T836	SQL/JSON path language: starts with predicate
❌ T837	SQL/JSON path language: regex_like predicate
❌ T838	JSON_TABLE: PLAN DEFAULT clause
❌ T839	Formatted cast of datetimes to/from character strings

1(1,2,3,4,5,6,7,8,9,10,11,12,13,14)

A conforming SQL-implementation is required to support at least one embedded language or to support the SQL-client module binding for at least one host language.

See Also

• ISO/IEC 9075-2:2016 - Information technology — Database languages — SQL — Part 2: Foundation (SQL/Foundation)

• SQL compliance on Wikipedia