SQL in a Nutshell, 3rd Edition

Supplemental Features Packages in the SQL3 Standard

The SQL3 standard represents the ideal, but very few vendors currently meet or exceed the Core SQL3 requirements. The Core standard is like the interstate speed limit: some drivers go above it and others go below it, but few go exactly the speed limit. Similarly, vendor implementations can vary greatly.

Two committees—one within ANSI, the other within ISO, and both composed of representatives from virtually every RDBMS vendor—drafted the supplemental feature definitions described in this section. In this collaborative and somewhat political environment, vendors compromised on exactly which proposed features and implementations would be incorporated into the new standard.

New features in the ANSI standard often are derived from an existing product or are the outgrowth of new research and development in the academic community. Consequently, vendor adoption of specific ANSI standards can be spotty. A relatively new addition to the SQL3 standard is SQL/XML (greatly expanded in SQL2006.) The other parts of the SQL99 standard remain in SQL3, though their names may have changed and they may have been slightly rearranged.

The nine supplemental features packages, representing different subsets of commands, are platform-optional. Some features might show up in multiple packages, while others do not appear in any of the packages. These packages and their features are described in the following list:

Part 1, SQL/Framework

Includes common definitions ...