Re: Performance Issue -- "Materialize"

I think you query is a bit confusing and have many subqueries, so I tried
to simplify

If you cant´t have more import_num = 0 to the same login, try this

SELECT count(*)
FROM test_tab tab1
LEFT JOIN test_tab tab2
ON tab1.login = tab2.login AND tab2.import_num = '0'
WHERE
tab2.login IS NULL AND
import_num = '4520440'

otherwise try this

SELECT count(*)
FROM test_tab tab1
LEFT JOIN (
SELECT DISTINCT login FROM test_tab WHERE import_num = '0'
) tab2
ON tab1.login = tab2.login
WHERE
tab2.login IS NULL AND
import_num = '4520440'

Em seg, 21 de ago de 2017 às 15:47, Carlos Augusto Machado <
caugustom(at)gmail(dot)com> escreveu:

>
> Do you have an index on login column ?
>
> If not, try creating an index and taking off those DISTICTs.
>
> Em seg, 21 de ago de 2017 às 15:33, Justin Pryzby <pryzby(at)telsasoft(dot)com>
> escreveu:
>
>> On Sat, Aug 19, 2017 at 10:37:56AM -0700, anand086 wrote:
>> >
>> +-----------------------------------------------------------------------------------------------------------------------------------------------------------+|
>> > QUERY PLAN
>> >
>> |+-----------------------------------------------------------------------------------------------------------------------------------------------------------+|
>> > Aggregate (cost=351405.08..351405.09 rows=1 width=8)
>>
>> Would you send explain ANALYZE and not just explain ?
>>
>> Justin
>>
>>
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>