Re: Checking if Aggregate exists

On Mar 24, 2008, at 1:09 PM, Martijn van Oosterhout wrote:
> On Mon, Mar 24, 2008 at 12:47:43PM -0500, Josh Trutwin wrote:
>> My code to check if an aggregate exists runs this query:
>>
>> SELECT * FROM pg_catalog.pg_aggretate WHERE aggfnoid =
>> 'foo'::REGPROC;
>
> Seems to me you'd rather want the proisagg column in pg_proc and
> forget
> about pg_aggregate altogether...

Also, the idiom for checking if something is present is normally:

SELECT 1 FROM some_table WHERE ...;

This way you aren't dealing with errors, if it doesn't exist the query
simply doesn't return any results.

Erik Jones

DBA | Emma®
erik(at)myemma(dot)com
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