[postgis-users] Problem with functions contains

[Miguel de la Fuente]

strk: I' have the following problem, when I use the function contains it
returns true when the polygons is not totally contains.
I have applied snaptogrid in my geometry column.
I did the following :
update table1 set new_geom=snaptogrid(the_geom,1e-2)
update table2 set new_geom=snaptogrid(the_geom,1e-2))
When I use the function contains()
 select
b.*
from table2 b, table1 a
where contains (b.new_geom,a.new_geom)
it returns true,but I see visually that b not contains completely a.
 I don't understand why??
  I attach the data and a image showing the problem.
 Thanks.
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