[postgis-devel] ST_Envelope & spatial index

[Andrea Peri]

>>* explain select ST_Extent(ST_Envelope(rast)) from raster.ofc10k_2010 limit 1;*>>* *>>* And see that.*>>* *>>* Limit  (cost=48027.93..48027.94 rows=1 width=32)*>>*   ->  Aggregate  (cost=48027.93..48027.94 rows=1 width=32)*>>*         ->  Seq Scan on ofc10k_2010  (cost=0.00..37419.53 rows=1414453*>>* width=32)*>>*

*>Try this:
>
>SELECT ST_Extent(rast::geometry) from raster.ofc10k_2010;
>
>Pierre

Hi, Pierre,
I test you query (with limit 1 to have same conditions).

SELECT ST_Extent(rast::geometry) from raster.ofc10k_2010 limit 1;


It report this cost:
It is rather the same.

Limit  (cost=44491.80..44491.81 rows=1 width=32)
  ->  Aggregate  (cost=44491.80..44491.81 rows=1 width=32)
        ->  Seq Scan on ofc10k_2010  (cost=0.00..37419.53 rows=1414453
width=32)


-- 
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Andrea Peri
. . . . . . . . .
qwerty àèìòù
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