David Rowley c399248b3b Fix deparsing of Consts in postgres_fdw ORDER BY
For UNION ALL queries where a union child query contained a foreign
table, if the targetlist of that query contained a constant, and the
top-level query performed an ORDER BY which contained the column for the
constant value, then postgres_fdw would find the EquivalenceMember with
the Const and then try to produce an ORDER BY containing that Const.

This caused problems with INT typed Consts as these could appear to be
requests to order by an ordinal column position rather than the constant
value.  This could lead to either an error such as:

ERROR:  ORDER BY position <int const> is not in select list

or worse, if the constant value is a valid column, then we could just
sort by the wrong column altogether.

Here we fix this issue by just not including these Consts in the ORDER
BY clause.

In passing, add a new section for testing ORDER BY in the postgres_fdw
tests and move two existing tests which were misplaced in the WHERE
clause testing section into it.

Reported-by: Michał Kłeczek
Reviewed-by: Ashutosh Bapat, Richard Guo
Bug: #18381
Discussion: https://postgr.es/m/0714C8B8-8D82-4ABB-9F8D-A0C3657E7B6E%40kleczek.org
Discussion: https://postgr.es/m/18381-137456acd168bf93%40postgresql.org
Backpatch-through: 12, oldest supported version
2024-03-11 12:27:11 +13:00
2024-02-28 15:17:23 +04:00
2019-12-18 09:13:13 +01:00
2022-12-04 15:23:00 -05:00
2024-01-03 20:49:05 -05:00
2020-02-10 20:47:50 +01:00
2024-02-28 15:17:23 +04:00
2024-02-28 14:53:52 -06:00

PostgreSQL Database Management System

This directory contains the source code distribution of the PostgreSQL database management system.

PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.

Copyright and license information can be found in the file COPYRIGHT.

General documentation about this version of PostgreSQL can be found at: https://www.postgresql.org/docs/devel/
In particular, information about building PostgreSQL from the source code can be found at: https://www.postgresql.org/docs/devel/installation.html

The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.

Description
No description provided
Readme 671 MiB
Languages
C 85.7%
PLpgSQL 5.8%
Perl 4.1%
Yacc 1.3%
Makefile 0.7%
Other 2.3%