Re: INOUT parameters in procedures

2018-03-13 14:14 GMT+01:00 Peter Eisentraut <
peter(dot)eisentraut(at)2ndquadrant(dot)com>:

> On 3/8/18 02:25, Pavel Stehule wrote:
> > It looks like some error in this concept. The rules for enabling
> > overwriting procedures should modified, so this collision should not be
> > done.
> >
> > When I using procedure from PL/pgSQL, then it is clear, so I place on
> > *OUT position variables. But when I call procedure from top, then I'll
> > pass fake parameters to get some result.
>
> What we'll probably want to do here is to make the OUT parameters part
> of the identity signature of procedures, unlike in functions. This
> should be a straightforward change, but it will require some legwork in
> many parts of the code.
>

yes

>
> > if (argmodes && (argmodes[i] == PROARGMODE_INOUT ||
> > argmodes[i] == PROARGMODE_OUT))
> > + {
> > + Param *param;
> >
> > Because PROARGMODE_OUT are disallowed, then this check is little bit
> > messy. Please, add some comment.
>
> Fixed.
>
> I discovered another issue, in LANGUAGE SQL procedures. Currently, if
> you make a CALL with an INOUT parameter in an SQL procedure, the output
> is thrown away (unless it's the last command). I would like to keep
> open the option of assigning the results by name, like we do in
> PL/pgSQL. So in this patch I have made a change to prohibit calling
> procedures with INOUT parameters in LANGUAGE SQL routines (see
> check_sql_fn_statements()). What do you think?
>

The disabling it, it is probably the best what is possible now. The
variables in SQL are more named parameters than variables. Is not necessary
to complicate it.

Regards

Pavel

>
> --
> Peter Eisentraut http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>