Can I improve performance by using the ANSI-style joins instead of the old-style joins?
Code Example 1: select o.name, i.name from sysobjects o, sysindexes i where o.id = i.id Code Example 2: select o.name, i.name from sysobjects o inner join sysindexes i on o.id = i.id You will not get any performance gain by switching to the ANSI-style JOIN syntax. Using the ANSI-JOIN syntax gives you an important advantage: Because the join logic is cleanly separated from the filtering criteria, you can understand the query logic more quickly. The SQL Server old-style JOIN executes the filtering conditions before executing the joins, whereas the ANSI-style JOIN reverses this procedure (join logic precedes filtering). Perhaps the most compelling argument for switching to the ANSI-style JOIN is that Microsoft has explicitly stated that SQL Server will not support the old-style OUTER JOIN syntax indefinitely. Another important consideration is that the ANSI-style JOIN supports query constructions that the old-style JOIN syntax does not support.
