Horton

Re: SQL-standard function body

Julien Rouhaud <rjuju123@gmail.com>

View thread View on postgr.es
From: Julien Rouhaud <rjuju123@gmail.com>
To: Jaime Casanova <jcasanov@systemguards.com.ec>
Cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-03-15T08:14:48Z
Lists: pgsql-hackers 
On Mon, Mar 15, 2021 at 04:03:44PM +0800, Julien Rouhaud wrote:
> On Mon, Mar 15, 2021 at 01:05:11AM -0500, Jaime Casanova wrote:
> > I found another problem when using CASE expressions:
> > 
> > CREATE OR REPLACE FUNCTION foo_case()
> > RETURNS boolean
> > LANGUAGE SQL
> > BEGIN ATOMIC
> >     select case when random() > 0.5 then true else false end;
> > END;
> > 
> > apparently the END in the CASE expression is interpreted as the END of
> > the function
> 
> I think that it's an issue in psql scanner.  If you escape the semicolon or
> force a single query execution (say with psql -c), it works as expected.

Applying the following diff (not sending a patch to avoid breaking the cfbot)
the issue and doesn't seem to break anything else:

diff --git a/src/fe_utils/psqlscan.l b/src/fe_utils/psqlscan.l
index a492a32416..58026fe90a 100644
--- a/src/fe_utils/psqlscan.l
+++ b/src/fe_utils/psqlscan.l
@@ -871,7 +871,9 @@ other           .

 {identifier}   {
                    cur_state->identifier_count++;
-                   if (pg_strcasecmp(yytext, "begin") == 0)
+                   if ((pg_strcasecmp(yytext, "begin") == 0)
+                       || (pg_strcasecmp(yytext, "case") == 0)
+                       )
                    {
                        if (cur_state->identifier_count > 1)
                            cur_state->begin_depth++;

Commits

  1. Don't crash on empty statements in SQL-standard function bodies.

  2. psql: Fix line continuation prompts for unbalanced parentheses

  3. Provide query source text when parsing a SQL-standard function body.

  4. Revert "Cope with NULL query string in ExecInitParallelPlan()."

  5. Undo decision to allow pg_proc.prosrc to be NULL.

  6. SQL-standard function body

  7. Move pg_stat_statements query jumbling to core.

  8. Extend SQL function tests lightly