Subject: Re: proposal: plpgsql, new check for extra_errors - strict_expr_check

From: Marcos Pegoraro <[email-masked]>
Date: Sun, 16 Jun 2024 11:22:02 -0300

Can you remove or just ignore double ; too ?

postgres=# do $$
declare var_x integer;
begin
  var_x = 99;;
  delete from x where x = var_x;
end; $$;
ERROR:  syntax error at or near ";"
LINE 1: do $$ declare var_x integer; begin var_x = 99;; delete from ...

Atenciosamente,

Em dom., 16 de jun. de 2024 às 11:12, Pavel Stehule <[email-masked]>
escreveu:

> Hi,
>
> assigned patch try to solve issue reported by Mor Lehr (Missing semicolon
> in anonymous plpgsql block does not raise syntax error).
>
>
> https://www.postgresql.org/message-id/CALyvM2bp_CXMH_Gyq87pmHJRuZDEhV40u9VP8rX=[email-masked]
>
> by introducing a new extra error check. With this check only a_expr exprs
> are allowed as plpgsql expressions. This is a small step to behaviour
> described in SQL/PSM standard (although the language is different, the
> expression syntax and features are almost similar. With this check the
> undocumented (but supported syntax)
>
> var := column FROM tab
>
> is disallowed. Only ANSI syntax for embedded queries (inside assignment
> statement) is allowed
>
> var := (SELECT column FROM tab);
>
> With this check, the reported issue (by Mor Lehr) is detected
>
> default setting
>
> CREATE TABLE foo3(id serial PRIMARY key, txt text);
> INSERT INTO foo3 (txt) VALUES ('aaa'),('bbb');
>
> DO $$
> DECLARE
>     l_cnt int;
> BEGIN
>     l_cnt := 1
>     DELETE FROM foo3 WHERE id=1;
> END; $$
>
> -- without reaction - just don't work
>
> (2024-06-16 16:05:55) postgres=# set plpgsql.extra_errors to
> 'strict_expr_check';
> SET
> (2024-06-16 16:06:43) postgres=# DO $$
>
> DECLARE
>     l_cnt int;
> BEGIN
>     l_cnt := 1
>     DELETE FROM foo3 WHERE id=1;
> END; $$;
> ERROR:  syntax error at or near "DELETE"
> LINE 11:     DELETE FROM foo3 WHERE id=1;
>              ^
>
> This patch has three parts
>
> 1. Introduction strict_expr_check
> 2. set strict_expr_check as default, and impact on regress tests
> 3. revert @2
>
> I don't propose to be strict_expr_check active  by default.
>
> Comments, notes?
>
> Regards
>
> Pavel
>
>
>