po 9. 8. 2021 v 23:13 odesílatel Tom Lane <tgl@xxxxxxxxxxxxx> napsal:
Pavel Stehule <pavel.stehule@xxxxxxxxx> writes:
> Some errors like this, but not this can be detected by plpgsql_check
> https://github.com/okbob/plpgsql_check - probably the heuristic for type
> check is not complete.
STRICTMULTIASSIGNMENT would detect most cases of this, except that
the condition is checked too late. We'd need to count the fields
*before* trying to assign values, not after.
In the meantime, it does seem like the docs could be more explicit
about this, and perhaps give an example showing the (x).* solution.
Yes, a more detailed explanation of this behavior can be nice. There can be an example of value unnesting, but I think so for this case, there should be mainly an example of ANSI assign syntax.
var := (SELECT x FROM ..)
This syntax has advantages so is not amigonuous for this case, and explicit unnesting is not necessary (and it is not possible). Moreover, this is ANSI SQL syntax.
Regards
Pavel
regards, tom lane