Re: function language type?

Ian Turner <iant@mail.brainstorm.net> writes:
>>>> with the error 'ERROR:  copyObject: don't know how to copy 611'. Does this
>>>> mean one is not permitted to create tables (even temporaries!) in a
>>>> function?
>>
>> At the moment, I think not.  There's no fundamental reason why it
>> couldn't be done, just some unfinished legwork (like writing a copy
>> subroutine for CreateStmt parse nodes...)

> OK. How hard would this be?

Actually I think the copyObject support may be the only missing piece.
But don't quote me.

> And just out of curiosity, why is the process different if one is in a
> function?

The issue with plpgsql is it wants to prepare a saved plan for SQL
commands, so they don't have to be re-planned on every call.  So that
means copying the parser output to someplace.  A lot of utility-class
statement parsenodes aren't in copyObject's repertoire for some
reason (laziness long ago no doubt).

> Can one create tables using the perl, C, or TCL interfaces?

Offhand I think this would work out-of-the-box in pltcl and plperl,
because they don't do preplanning.  This is also why you can do
something like "SELECT ... FROM $1" in those PLs and not in plpgsql:
they just form the command as a string and then run it through the
whole parse/plan process every time.

And of course you can do anything you want in C, if you don't mind
the learning curve.

            regards, tom lane