Tom Lane wrote:
Given that it estimated 1 row out of words (quite correctly) and 12264
rows out of each scan on article_words, you'd think that the join size
estimate would be 12264, which would be off by only a factor of 3 from
the true result. Instead it's 23, off by a factor of 200 :-(.
On Wed, Feb 10, 2010 at 8:52 PM, Bryce Nesbitt bry...@obviously.com wrote:
If you guys succeed in making this class of query perform, you'll have beat
out the professional consulting firm we hired, which was all but useless!
The query is usually slow, but particular combinations of words seem
Or, if you want to actually read that query plan, try:
http://explain.depesz.com/s/qYq
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2010/2/10 Bryce Nesbitt bry...@obviously.com:
Or, if you want to actually read that query plan, try:
http://explain.depesz.com/s/qYq
hello,
check your work_mem sesttings. Hash join is very slow in your case.
Pavel
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On Wed, Feb 10, 2010 at 3:29 AM, Bryce Nesbitt bry...@obviously.com wrote:
Or, if you want to actually read that query plan, try:
http://explain.depesz.com/s/qYq
Much better, though I prefer a text attachment... anyhow, I think the
root of the problem may be that both of the subquery scans
That sure looks like the source of the problem to me too. I've seen similar
behavior in queries not very different from that. It's hard to guess what the
problem is exactly without having more knowledge of the data distribution in
article_words though.
Given the results of analyze, I'd try to
If you guys succeed in making this class of query perform, you'll have
beat out the professional consulting firm we hired, which was all but
useless! The query is usually slow, but particular combinations of
words seem to make it obscenely slow.
The query plans are now attached (sorry I did not
Bryce Nesbitt bry...@obviously.com writes:
The query plans are now attached (sorry I did not start there: many
lists reject attachments). Or you can click on text at the query
planner analysis site http://explain.depesz.com/s/qYq
At least some of the problem is the terrible quality of the
