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Re: Planner selects slow "Bitmap Heap Scan" when "Index Scan" is faster - Mailing list pgsql-performance

From Kevin Grittner
Subject Re: Planner selects slow "Bitmap Heap Scan" when "Index Scan" is faster
Date
Msg-id 4F7D753C0200002500046BF5@gw.wicourts.gov
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In response to Planner selects slow "Bitmap Heap Scan" when "Index Scan" is faster  (Kim Hansen <kim@rthansen.dk>)
Responses Re: Planner selects slow "Bitmap Heap Scan" when "Index Scan" is faster  (Kim Hansen <kim@rthansen.dk>)
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Kim Hansen <kim@rthansen.dk> wrote:

> I have a query where the planner makes a wrong cost estimate, it
> looks like it underestimates the cost of a "Bitmap Heap Scan"
> compared to an "Index Scan".

> What can I do to fix the cost estimate?

Could you try running the query with cpu_tuple_cost = 0.05 and let
us know how that goes?

-Kevin

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