Jeremy Harris wrote:
John Beaver wrote:
I'm having a strange problem with a query. The query is fairly
simple, with a few constants and two joins. All relevant columns
should be indexed, and I'm pretty sure there aren't any type
conversion issues. But the query plan includes a fairly heavy seq
scan. The only possible complication is that the tables involved are
fairly large - hundreds of millions of rows each.
Can anyone explain this? There should only ever be a maximum of about
50 rows returned when the query is executed.
You didn't say when you last vacuumed?
I ran 'vacuum analyze' on both tables directly after I finished building
them, and I haven't updated their contents since.
If there should only be 50 rows returned then the estimates from the
planner are way out.
If that doesn't help, we'll need version info, and (if you can afford
the time) an "explain analyze"
Sure, I'm running it now. I'll send the results when it's done, but yes,
it could take a while.
Cheers,
Jeremy
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