Re: VACUUM ANALYZE downgrades performance

    Hi Rod!

 Thomas> Index scans are not always faster, and the planner/optimizer knows
 Thomas> this.  VACUUM ANALYZE is best run when a large proportion of data
 Thomas> has been updated/loaded or in the off hours to refresh the
 Thomas> statistics on large datasets.
 >>  While I agree that generally this is true, look how stupid this
 >> behavior looks in this particular case: A developer creates a table and
 >> index, knowing that the table will be large and will be intensively
 >> used. An admin runs 'VACUUM ANALYZE' when table is occasionally empty,
 >> and next, say, 1 day, until another 'VACUUM ANALYZE' starts, the index
 >> is simply not used! Sure you don't suppose to run 'VACUUM ANALYZE'
 >> every 5 minutes as a solution, right?

 Rod> You might want to try this on the next 8.0 beta to come out, or
 Rod> against CVS. Tom recently applied some changes which should mitigate
 Rod> this situation.

But this would affect only VACUUM, and not ANALYZE, right?

--
Sincerely,
    Dmitry Karasik

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