Re: sub-select in IN clause results in sequential scan - Mailing list pgsql-performance

On Wed, Oct 28, 2009 at 6:13 PM, Anj Adu <fotographs@gmail.com> wrote:

Postgres consistently does a sequential scan on the child partitions
for this query

select * from partitioned_table
where partitioned_column > current_timestamp - interval 8 days
where x in (select yy from z where colname like 'aaa%')

If I replace the query with

select * from partitioned_table
where partitioned_column > current_timestamp - interval 8 days
where x in (hardcode_value)

The results are in line with expectation (very fast and uses a Bitmap
Index Scan on the column X)

\

use JOIN luke..

 

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GJ