Re: Row pattern recognition

From: Tatsuo Ishii <ishii(at)postgresql(dot)org>
To: assam258(at)gmail(dot)com
Cc: zsolt(dot)parragi(at)percona(dot)com, vik(at)postgresfriends(dot)org, er(at)xs4all(dot)nl, jacob(dot)champion(at)enterprisedb(dot)com, david(dot)g(dot)johnston(at)gmail(dot)com, peter(at)eisentraut(dot)org, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Row pattern recognition
Date: 2026-03-12 00:21:25
Message-ID: 20260312.092125.2016894123875469735.ishii@postgresql.org
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Hi Zsolt,

Thanks for the report and the test case!

> Good catch, Zsolt. You're right ― the return value of
> coerce_to_boolean() must be assigned back to te->expr, otherwise
> any implicit cast (e.g., a user-defined type with an assignment
> cast to boolean) is silently discarded.
>
> The fix is straightforward:
>
> foreach_ptr(TargetEntry, te, defineClause)
> te->expr = (Expr *) coerce_to_boolean(pstate, (Node *) te->expr,
> "DEFINE");
>
> I've confirmed that your example query produces incorrect results
> without the fix (the truthyint value is evaluated as-is without
> the cast) and correct results with it.
>
> Patch 13 is attached with the fix and a regression test case based
> on your example.

Yeah, current patch needs to be fixed. Question is, the output of the
expression of DEFINE clause must be a strict boolean or, it is allowed
to accept an expression coercive to boolean?

If we prefer the former, we should use exprType() instead.

Best regards,
--
Tatsuo Ishii
SRA OSS K.K.
English: http://www.sraoss.co.jp/index_en/
Japanese:http://www.sraoss.co.jp

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Henson Choi 2026-03-12 00:39:57 Re: Row pattern recognition
Previous Message Chao Li 2026-03-12 00:08:39 Re: Add documentation for PG_ABS_SRCDIR, PG_ABS_BUILDDIR, PG_LIBDIR, PG_DLSUFFIX