SQL92

SQL-92, also known as SQL2, is a major revision of the SQL standard for relational database management systems. It was published in 1992 by ANSI and ISO as ISO/IEC 9075-2 and served as the core standard for the SQL language, superseding the earlier SQL-89 baseline. The standard aimed to provide a comprehensive, vendor-neutral specification that could be implemented across different database systems.

Scope and features: SQL-92 covers data query, data manipulation, data definition, and access control. It formalized a range of integrity mechanisms, including primary keys, foreign keys, and check constraints, and introduced support for views and transaction controls such as COMMIT and ROLLBACK. It standardized information about data types and built-in functions, and it codified the semantic rules that govern SQL statements.

It also expanded capabilities for complex queries, including subqueries, set operations, and the use of explicit join syntax (INNER and OUTER joins). These enhancements helped unify querying approaches across platforms and reduced reliance on vendor-specific extensions.

Impact and legacy: SQL-92 quickly became the de facto baseline for commercial RDBMS. It shaped subsequent language revisions and remains a reference point for compatibility, though many systems extended the standard with vendor-specific features. The standard was superseded by later editions, beginning with SQL:1999.

Technical notes: The SQL-92 standard is part of ISO/IEC 9075 and is often referred to as SQL-92 or SQL2. It is widely cited in historical discussions of database features and as the historical baseline for modern SQL dialects.

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