polygon info

I have a table created with an attribute of polygon datatype.

7.2 seems to have overcome a tuple size limit in 7.1.x which is nice.

The doc's don't go into much detail about geometric operators & functions.

Can PG return the area of a polygon? The docs suggest it can (at least
for box data), but this suggests it can't.

>geotest=# select area(list)from test1;
>ERROR:  Function 'area(polygon)' does not exist
>        Unable to identify a function that satisfies the given argument
>types
>        You may need to add explicit typecasts

Boxing the polygon to return the area won't quite do what I want :-)

Also, is there any further info available on indexing & performance
tweaking for geometric datatypes?

Thanks....

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       _-''-_    <Brent Wood> b.wood@niwa.cri.nz  Ph: +64(4)386-0300
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