Tom Lane 3f50b82639 Fix EXPLAIN to handle SEARCH BREADTH FIRST queries.
The rewriter transformation for SEARCH BREADTH FIRST produces a
FieldSelect on a Var of type RECORD, where the Var references the
recursive union's worktable output.  EXPLAIN VERBOSE failed to handle
this case, because it only expected such Vars to appear in CteScans
not WorkTableScans.  Fix that, and add some test cases exercising
EXPLAIN on SEARCH and CYCLE queries.

In principle this oversight is an old bug, but it seems that the
case is unreachable without SEARCH BREADTH FIRST, because the
parser fails when attempting to create such a reference manually.
So for today I'll just patch HEAD/v14.  Someday we might find that
the code portion of this patch needs to be back-patched further.

Per report from Atsushi Torikoshi.

Discussion: https://postgr.es/m/5bafa66ad529e11860339565c9e7c166@oss.nttdata.com
2021-09-16 10:45:42 -04:00
2019-12-18 09:13:13 +01:00
2021-01-02 13:06:25 -05:00
2020-02-10 20:47:50 +01:00
2020-02-10 20:47:50 +01:00
2020-02-10 20:47:50 +01:00

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.

PostgreSQL has many language interfaces, many of which are listed here:

	https://www.postgresql.org/download/

See the file INSTALL for instructions on how to build and install
PostgreSQL.  That file also lists supported operating systems and
hardware platforms and contains information regarding any other
software packages that are required to build or run the PostgreSQL
system.  Copyright and license information can be found in the
file COPYRIGHT.  A comprehensive documentation set is included in this
distribution; it can be read as described in the installation
instructions.

The latest version of this 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
he World's Most Advanced Open Source Relational Database.
Readme 742 MiB
Languages
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PLpgSQL 5.9%
Perl 4.4%
Yacc 1.2%
Meson 0.7%
Other 2.2%