Re: BUG #18463: Possible bug in stored procedures with polymorphic OUT parameters

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>

To: Dmitry Dolgov <9erthalion6@gmail.com>

Cc: drewk@cockroachlabs.com, pgsql-bugs@lists.postgresql.org

Date: 2024-05-14T19:35:37Z

Lists: pgsql-bugs

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Fix failure with SQL-procedure polymorphic output arguments in v12.
- d88dcdf0fa5b 14.13 landed
- bb331af4aeb7 16.4 landed
- 9de0ff91a501 13.16 landed
- 751598263690 17.0 landed
- 5fe43d41db59 15.8 landed
- 4208f44c9469 12.20 landed
Fix handling of polymorphic output arguments for procedures.
- f535f350c1f9 17.0 landed
- e85f641b2b52 13.16 landed
- c40e78d239a8 15.8 landed
- 8e0e99972ad9 16.4 landed
- 70ffb27b2349 12.20 landed
- 525bd1620e9b 14.13 landed

Attachments

fix-polymorphic-procedure-outputs.patch (text/x-diff) patch

I wrote:
> It looks like we'd have to teach resolve_polymorphic_tupdesc how
> to get argument types out of a CallExpr, so that does not lead
> to an entirely trivial fix, but it's surely possible.

> Maybe it'd be better to not try to use build_function_result_tupdesc_t
> here at all.  It looks to me like the output argument list in the
> CallStmt is already fully polymorphically resolved, so we could just
> build a tupdesc based on that and probably save a lot of work.

Some experimentation showed that we need to return the correct
output column names in this tupdesc, so continuing to use
build_function_result_tupdesc_t seems like the easiest path for that.
However, stmt->outargs does hold nodes of the correct resolved data
types, so overwriting the atttypid's from that produces a nicely
small patch, as attached.

			regards, tom lane