Transact-SQL Outer Joins Support

Supported syntax for outer joins differs between Adaptive Server Enterprise, SQL Anywhere, and Sybase IQ.

Adaptive Server Enterprise fully supports *= and =* Transact-SQL syntax for outer joins.
SQL Anywhere and Sybase IQ support Transact-SQL outer joins, but reject some complex Transact-SQL outer joins that are potentially ambiguous.
Sybase IQ does not support chained (nested) Transact-SQL outer joins. Use ANSI syntax for this type of multiple outer join.

Note: Transact-SQL outer join syntax is deprecated in SQL Anywhere and Sybase IQ.

For detailed information on Transact-SQL outer joins, including ANSI syntax alternatives, see the white paper “Semantics and Compatibility of Transact-SQL Outer Joins,” from MySybase. Although written for SQL Anywhere, the information in the document also applies to Sybase IQ.