"Paul Mathews" <plm@netspace.net.au> writes:
> Despite the existence of the index, postgresql is determined to full table
> scan when given.
> SELECT
> postcode
> WHERE
> boundary @> point 'x,y';
polygon @> point isn't an indexable operator. The indexable operators
for a gist index on polygon are
<<(polygon,polygon)
&<(polygon,polygon)
&&(polygon,polygon)
&>(polygon,polygon)
>>(polygon,polygon)
~=(polygon,polygon)
@>(polygon,polygon)
<@(polygon,polygon)
&<|(polygon,polygon)
<<|(polygon,polygon)
|>>(polygon,polygon)
|&>(polygon,polygon)
~(polygon,polygon)
@(polygon,polygon)
So it looks like you need to convert the point to a one-point polygon.
regards, tom lane