At 2006-11-10 01:15:24 -0500, tgl@xxxxxxxxxxxxx wrote: > > it seems that "field<=12" is true for a much smaller fraction of the > rows satisfying (part!='' or value ilike '%,%') than for the general > population of rows in the header_fields table. Indeed. One-sixth of the rows in the entire table match field<=12, but only one-fifteenth of the rows matching the part/value condition also match field<=12. > There's been some speculation about obtaining stats on partial indexes > as a substitute for solving the general problem of correlation stats, Oh. So my partial index's rowcount isn't being considered at all? That explains a lot. Ok, I'll just run the query with mergejoin and seqscan disabled. (I can't think of much else to do to speed it up, anyway.) Thanks. -- ams
