> Add the MATERIALIZED keyword to the WITH statement
Many thanks Jim, that's just what I needed - that does the trick.
It's hard to keep abreast of these SQL changes. Thank goodness for mailing lists!
Steve
On Thu, 16 Sept 2021 at 11:56, Jim Mlodgenski <jimmy76@gmail.com> wrote:
On Thu, Sep 16, 2021 at 4:51 AM Steve Pritchard <steve.pritchard@bto.org> wrote: > > I have a PL/pgSQL function that I want to call within a query, but the function is fairly expensive to execute so I only want it executed once within the query. However the planner seems to reorganize my query so that it calls the function for every row. > > We were previously on Pg 9.6 and this wasn't a problem then. But now that we have upgraded to Pg 13, the behaviour has changed. >
The behavior for planning a CTE changed in PG12.
> There must be a "proper" way to get the planner to call a function only once. > Add the MATERIALIZED keyword to the WITH statement
--
Steve Pritchard
Database Developer
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