Comparison of different SQL implementations
This page compares how different database management systems (PostgreSQL, DB2, MS SQL Server, MySQL, Oracle, and Informix) implement various SQL features and operations, showing which products follow the SQL standard and where they diverge. It covers everything from basic SELECT and INSERT syntax to data types, functions, metadata queries, and command-line operations, serving as a practical guide for developers porting SQL code between different database platforms. The author acknowledges the page is no longer actively maintained but provides extensive side-by-side feature comparisons with code examples for each DBMS's approach to standard SQL functionality.