Re: Index scan startup time

["Steinar H. Gunderson" <sgunderson(at)bigfoot(dot)com>]

On Thu, Mar 30, 2006 at 01:59:10PM +0200, Peter Eisentraut wrote:
> EXPLAIN ANALYZE select activity_id from activity where state in (10000, 10001) 
> order by activity_id limit 100;
> 
> QUERY PLAN
> 
> Limit  (cost=0.00..622.72 rows=100 width=8) (actual 
> time=207356.054..207356.876 rows=100 loops=1)
>   ->  Index Scan using activity_pk on activity  (cost=0.00..40717259.91 
> rows=6538650 width=8) (actual time=207356.050..207356.722 rows=100 loops=1)
>         Filter: ((state = 10000) OR (state = 10001))
> Total runtime: 207357.000 ms
> 
> The table has seen VACUUM FULL and REINDEX before this.

The index scan is by activity_id, not by state. Do you have an index on state
at all?

/* Steinar */
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