Re: difference in plan between 8.0 and 8.1?

From: Michael Fuhr
Subject: Re: difference in plan between 8.0 and 8.1?
Date: ,
Msg-id: 20050826151608.GA16945@winnie.fuhr.org
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In response to: difference in plan between 8.0 and 8.1?  (Alan Stange)
List: pgsql-performance

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difference in plan between 8.0 and 8.1?  (Alan Stange, )
 Re: difference in plan between 8.0 and 8.1?  (Tom Lane, )
  Re: difference in plan between 8.0 and 8.1?  (Alan Stange, )
 Re: difference in plan between 8.0 and 8.1?  (Michael Fuhr, )
 Re: difference in plan between 8.0 and 8.1?  ("Merlin Moncure", )

On Fri, Aug 26, 2005 at 10:45:07AM -0400, Alan Stange wrote:
>         ->  Bitmap Heap Scan on tbltimeseries (cost=48714.09..1331000.42 rows=10854026 width=8)
>               Recheck Cond: (timeseriesid > 0)
>               ->  Bitmap Index Scan on idx_timeseris (cost=0.00..48714.09 rows=10854026 width=0)
>                     Index Cond: (timeseriesid > 0)
>
> I'm hoping someone can explain the new query plan (as I'm not sure I
> understand what it is doing).

Search for "bitmap" in the 8.1 Release Notes:

http://developer.postgresql.org/docs/postgres/release.html#RELEASE-8-1

You could probably find more detailed discussion in the pgsql-hackers
archives.

--
Michael Fuhr


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