| From: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Jules Bean <jules(at)jellybean(dot)co(dot)uk>, Alfred Perlstein <bright(at)wintelcom(dot)net>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Performance on inserts |
| Date: | 2000-10-15 21:55:22 |
| Message-ID: | 200010152155.RAA16583@candle.pha.pa.us |
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| Lists: | pgsql-hackers |
> > > * Prevent index lookups (or index entries using partial index) on most
> > > common values; instead use sequential scan
> >
> > This behavior already exists for the most common value, and would
> > exist for any additional values that we had stats for. Don't see
> > why you think a separate TODO item is needed.
>
> You mean the optimizer already skips an index lookup for the most common
> value, and instead does a sequential scan? Seems you are way ahead of
> me.
If the answer is yes, how do you prevent a join that hits the most
common value?
--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
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