On Sat, Aug 27, 2005 at 11:05:01AM -0400, Tom Lane wrote: > It could, but it doesn't really have enough information. We don't > currently have any model that some operators are more expensive than > others. IIRC the only sort of reordering the current code will do > in a filter condition list is to push clauses involving sub-SELECTs > to the end.
I was more thinking along the lines of reordering "a AND/OR b" to "b AND/OR a" if b has lower selectivity than a. /* Steinar */ -- Homepage: http://www.sesse.net/ ---------------------------(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
