Re: Unexpected query plan results

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Robert Haas wrote:

On Thu, May 28, 2009 at 6:46 PM, Anne Rosset <arosset@xxxxxxxxxx> wrote:
                                                ->  Index Scan using
item_pk on item  (cost=0.00..176865.31 rows=97498 width=88) (actual
time=117.304..2405.060 rows=71 loops=1)
                                                      Filter: ((NOT
is_deleted) AND ((folder_id)::text = 'tracker3641'::text))

The fact that the estimated row count differs from the actual row
count by a factor of more than 1000 is likely the root cause of your
problem here.  You probably want to figure out why that's happening.
How many rows are in that table and what value are you using for
default_statistics_target?

...Robert

The table has 468173 rows and the value for default_statistics_target is 750.
Anne

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