Re: Problem analyzing performance of query

Greg Stark <gsstark@mit.edu> writes:
> Is there any way to ask the server what plan it's using when it's actually
> executing the query in production, rather than trying to feed it the same
> query later in another context and hope it gets the same result?

From the planner's point of view, a plpgsql query involving plpgsql
variables is a parameterized query, which is the same as a PREPAREd
query with parameters.  So for instance

    create function foo(int) ...
    ...
       select ... where keycol = $1;
    ...

looks the same as

    PREPARE q(int) AS select ... where keycol = $1;

and you can investigate the plan for this with

    EXPLAIN [ANALYZE] EXECUTE q(42);

Clear?  It'd be nice to have more infrastructure for debugging plpgsql
code, but so far no one's got round to building any :-(

            regards, tom lane