Summary information |
|
|---|---|
Default value |
0 |
Range of values |
0–1 |
Status |
Dynamic |
Display level |
Comprehensive |
Required role |
System Administrator |
enable sort-merge joins and JTC configuration parameter determines whether merge joins and join transitive closure are considered by the query optimizer. By default, merge joins and join transitive closure are not enabled. To enable merge joins, set this parameter to 1.
Merge joins and join transitive closure can improve performance for queries that access large amounts of data, but increase optimization time. The session-level options set sort-merge on and set jtc on take precedence over the server-wide setting. For more information, see Chapter 3, “Advanced Optimizing Tools” in Performance and Tuning: Optimizer and Abstract Plans.
