Re: Slow query after upgrade from 9.0 to 9.2

On 10.01.2013 19:48, Matheus de Oliveira wrote:
>
>
> On Thu, Jan 10, 2013 at 11:32 AM, Andrzej Zawadzki <zawadaa@wp.pl
> <mailto:zawadaa@wp.pl>> wrote:
>
>     Hi!
>
>     Small query run on 9.0 very fast:
>
>     SELECT * from sygma_arrear sar where sar.arrear_import_id = (
>             select sa.arrear_import_id from sygma_arrear sa,
>     arrear_import ai
>             where sa.arrear_flag_id = 2
>             AND sa.arrear_import_id = ai.id <http://ai.id>
>             AND ai.import_type_id = 1
>             order by report_date desc limit 1)
>         AND sar.arrear_flag_id = 2
>         AND sar.credit_id = 3102309 <tel:3102309>
>
>     "Index Scan using sygma_arrear_credit_id on sygma_arrear sar
>     (cost=0.66..362.03 rows=1 width=265)"
>     "  Index Cond: (credit_id = 3102309 <tel:3102309>)"
>     "  Filter: ((arrear_import_id = $0) AND (arrear_flag_id = 2))"
>     "  InitPlan 1 (returns $0)"
>     "    ->  Limit  (cost=0.00..0.66 rows=1 width=8)"
>     "          ->  Nested Loop  (cost=0.00..3270923.14 rows=4930923
>     width=8)"
>     "                ->  Index Scan Backward using report_date_bank_id_key
>     on arrear_import ai  (cost=0.00..936.87 rows=444 width=8)"
>     "                      Filter: (import_type_id = 1)"
>     *"                ->  Index Scan using
>     sygma_arrear_arrear_import_id_idx
>     on sygma_arrear sa  (cost=0.00..6971.15 rows=31495 width=4)"**
>     **"                      Index Cond: (sa.arrear_import_id = ai.id
>     <http://ai.id>)"**
>     **"                      Filter: (sa.arrear_flag_id = 2)"**
>     *
>     Engine uses index - great.
>
>     On 9.2
>
>     "Index Scan using sygma_arrear_credit_id on sygma_arrear sar
>     (cost=11.05..381.12 rows=1 width=265)"
>     "  Index Cond: (credit_id = 3102309 <tel:3102309>)"
>     "  Filter: ((arrear_import_id = $0) AND (arrear_flag_id = 2))"
>     "  InitPlan 1 (returns $0)"
>     "    ->  Limit  (cost=0.00..11.05 rows=1 width=8)"
>     "          ->  Nested Loop  (cost=0.00..54731485.84 rows=4953899
>     width=8)"
>     "                Join Filter: (sa.arrear_import_id = ai.id
>     <http://ai.id>)"
>     "                ->  Index Scan Backward using report_date_bank_id_key
>     on arrear_import ai  (cost=0.00..62.81 rows=469 width=8)"
>     "                      Filter: (import_type_id = 1)"
>     *"                ->  Materialize  (cost=0.00..447641.42 rows=6126357
>     width=4)"**
>     **"                      ->  Seq Scan on sygma_arrear sa
>     (cost=0.00..393077.64 rows=6126357 width=4)"**
>     **"                            Filter: (arrear_flag_id = 2)"**
>     *
>     Seq scan... slooow.
>
>     Why that's happens? All configurations are identical. Only engine is
>     different.
>
>
>
> How did you do the upgrade?
pg_upgrade and I think that this is source of problem.
I have test database from dump/restore process and works properly.
> Have you tried to run a VACUUM ANALYZE on sygma_arrear?
Yes I did - after upgrade all databases was vacuumed.

vacuumdb -azv

I'll try reindex all indexes at weekend

--
Andrzej Zawadzki