On Thu, Sep 3, 2009 at 3:44 AM, Allan Kamau <kamauallan@gmail.com> wrote:
> Hi,
> I do have a query which make use of the results of an aggregate
> function (for example bit_or) several times in the output column list
> of the SELECT clause, does PostgreSQL simply execute the aggregate
> function only once and provide the output to the other calls to the
> same aggregate function.
> How about the case of non volatile functions? Do they get executed as
> many times as they occur in the select clause?
I don't think so...could you provide a better example? It sounds like
your query is one that might benefit from use of CTE...
merlin
