Re: Return unknown resultset from a function

On Mon, Mar 5, 2012 at 10:08 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Merlin Moncure <mmoncure(at)gmail(dot)com> writes:
>> The only exception to this rule is cursors.  Reading from cursors via
>> FETCH allows you to pull data from a refcursor that was set up in a
>> previous function call and works pretty well, but comes with the giant
>> downside that the results can be directed only to the client.
>
> Hmm, couldn't you do a FETCH into a record variable in plpgsql?  Not
> that you'd not have problems manipulating the record variable, since
> plpgsql is pretty strongly typed itself.

Yeah -- good point on both sides -- you can do it, but it's pretty
limiting: you can only fetch a row at a time and the result data can't
be further expressed in another query. A CTE based FETCH has been
suggested a couple of times as a hypothetical workaround.

Whether the data is processed on the server or the client the result
essentially the result is the same...you're forced into a highly
iterative method of programming that I try to avoid whenever possible.

TBH though I find the textual workarounds to the type system to work
pretty well, meaning that most of the useful things which were
historically only possible in C have been nicely wrapped or seem to be
just plain impossible (like handling mixed type variadic functions, or
receiving generic RECORDs as arguments).

merlin