plpgsql - execute - cannot use a reference to record field

Pavel Stehule <pavel.stehule@gmail.com> writes:

Is there reason why following code should not to work?

do $$
declare r record; result int;
begin
select 10 as a, 20 as b into r;
raise notice 'a: %', r.a;
execute 'select $1.a + $1.b' into result using r;
raise notice '%', result;
end;
$$

You can't select fields by name out of an unspecified record.
The EXECUTE'd query is not particularly different from

regression=# prepare foo(record) as select $1.a + $1.b;
psql: ERROR: could not identify column "a" in record data type
LINE 1: prepare foo(record) as select $1.a + $1.b;
^

and surely you wouldn't expect that to work.
(The fact that either of the previous lines work is
thanks to plpgsql-specific hacking.)

regards, tom lane

po 15. 4. 2019 v 18:07 odesílatel Tom Lane <tgl@sss.pgh.pa.us> napsal:

Pavel Stehule <pavel.stehule@gmail.com> writes:

Is there reason why following code should not to work?

do $$
declare r record; result int;
begin
select 10 as a, 20 as b into r;
raise notice 'a: %', r.a;
execute 'select $1.a + $1.b' into result using r;
raise notice '%', result;
end;
$$

You can't select fields by name out of an unspecified record.
The EXECUTE'd query is not particularly different from

regression=# prepare foo(record) as select $1.a + $1.b;
psql: ERROR: could not identify column "a" in record data type
LINE 1: prepare foo(record) as select $1.a + $1.b;
^

and surely you wouldn't expect that to work.
(The fact that either of the previous lines work is
thanks to plpgsql-specific hacking.)

yes. I looking to the code and I see so SPI_execute_with_args doesn't allow
push typmods there.

Regards

Pavel