[postgis-users] Very long query time

[Tumasgiu Rossini]

And I am not really sure that what you are willing to achieve with the
GROUP BY
I am not aware of you data model, though.

Maybe you have upgraded recently to postgis 2.4 which change GROUP BY
behavior
when it comes to geometries [1]?
Geometries in 2.4 are no more grouped using bbox comparison but using
strict equality (st_equals)

[1]http://blog.cleverelephant.ca/2017/09/postgis-operators.html


Le jeu. 6 déc. 2018 à 17:09, Tumasgiu Rossini <rossini.t at gmail.com> a
écrit :

> I do not really understand.
> Is it a query which used to be faster ?
>
> A little remark on your where clause :
> it is unnecesseraly complicated and could be shortened to :
>     WHERE st_intersects(zi.geom, tile.geom)
>
> True and false value doesn't need to be surronded by quote,
> here you are implicitly casting the string value 'true' to its boolean
> representation
>
>
> Le jeu. 6 déc. 2018 à 16:53, Manchon Pierre <pierre.manchon at irstea.fr> a
> écrit :
>
>> Hello there,
>>
>> I'm new on the list and for a premiere I would like to know if some of
>> you have a very long runtime for some of their queries (even with a LIMIT
>> 5), whereas those queries were working well before (nothing changed from
>> that).  I'm using Postgre10, pgAdmin4 and postgis 2.4.4 on windows …
>>
>>
>>
>> The infinite query I’m trying to execute: (only ~500 rows are stored on
>> each of the two tables)
>>
>>
>>
>> SELECT code_tile, code_zi FROM data.tile, data.zi
>>
>> WHERE ST_Intersects(zi.geom, tile.geom) = 'true'
>>
>> GROUP BY code_zi, code_tile, zi.geom, tile.geom
>>
>> LIMIT 5
>>
>>
>>
>> Thank you for your time
>> _______________________________________________
>> postgis-users mailing list
>> postgis-users at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/postgis-users
>
>
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