"David G. Johnston" <david.g.johnston@gmail.com> writes:
> Yes, SQL and pl/pgsql have very different behaviors when it comes to
> compilation and execution. In particular SQL performs parsing earlier
> (during creation - just like it does for views) and links the textual query
> to its parse result earlier. For pl/pgsql none of that happens until the
> function is called. Because of this pl/pgsql allows for ambiguous sql text
> to exist and be concretely resolved during execution while SQL does not.
I don't think that's accurate. SQL functions are stored as plain text,
just like any other non-C-coded function, and they are not parsed until
execution.
There are big differences from plpgsql of course. For one, it's
possible for a SQL function to be "inlined" into the calling query,
in which case parsing happens during planning of the calling query.
But other than that, I'd expect the execution-time search path
to determine how a SQL function behaves.
Since Rob didn't provide any details, it's far from clear what's
going wrong for him.
regards, tom lane