Alexander, On 11/7/07, Alexander Staubo <[EMAIL PROTECTED]> wrote: > That's a difference of less than *three milliseconds* -- a difference > probably way within the expected overhead of running "explain > analyze". Furthermore, all three queries use the same basic plan: a > sequential scan with a filter. At any rate you're microbenchmarking in > a way that is not useful to real-world queries. In what way are these > timings a problem?
If you read my previous email carefully, you'll see they aren't a problem: the problem is the estimation, not the timing. This is a self contained test case of a far more complex query which uses a bad plan containing a nested loop due to the bad estimate. > Now all "like 'prefix%'" queries should use the index. Not when you retrieve 50% of this table of 22k rows but that's not my problem anyway. A seqscan is perfectly fine in this case. Thanks anyway. -- Guillaume ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
