"Mark Liberman" <[EMAIL PROTECTED]> writes: > I have recently implemented table partitioning in our postgres 8.1 db. = > Upon analyzing query performance, I have realized that, even when only a = > single one of the "partitions" has to be scanned, the plan is = > drastically different, and performs much worse, when I query against the = > master table (uses merge join), vs. a direct query against the partition = > directly (uses a hash join). The majority of our queries only access a = > single partition.
Joins against partitioned tables suck in 8.1 :-(. There is code in CVS HEAD to improve this, but it didn't get done in time for 8.1. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match