[postgis-users] about range query

[superman0920]

hi
I have over 8500000 records in the postgresql and every record has a geom column what is store a point.
I get a point coordinate(eg 116.1124,39.9046 ) and I want to know the coordinates of db points which is in 500m range.

I use 
ST_Distance(
the_geom,
'srid=4326;point(116.1124 39.9046)'
) <= 500
but the query is very slow(about take 15s)

Is there some another way can do fast ?




superman0920
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