postgres

Tom Lane 1f91c8ca1d Avoid planner crash/Assert failure with joins to unflattened subqueries. examine_simple_variable supposed that any RTE_SUBQUERY rel it gets pointed at must have been planned already. However, this isn't a safe assumption because we must do selectivity estimation while generating indexscan paths, and that code might look at join clauses involving a rel that the loop in set_base_rel_sizes() hasn't reached yet. The simplest fix is to play dumb in such a situation, that is give up trying to extract any stats for the Var. This could possibly be improved by making a separate pass over the RTE list to plan each unflattened subquery before we start the main planning work --- but that would be pretty invasive and it doesn't seem worth it, for now at least. (We couldn't just break set_base_rel_sizes() into two loops: the prescan would need to handle all subquery rels in the query, not only those in the current join subproblem.) This bug was introduced in commit `1cb108efb0`, although I think that subsequent changes may have exposed it more than it was originally. Per bug #7580 from Maxim Boguk.		14 years ago
config	Add infrastructure for compile-time assertions about variable types.	14 years ago
contrib	Add --sampling-rate option to pgbench.	14 years ago
doc	Add --sampling-rate option to pgbench.	14 years ago
src	Avoid planner crash/Assert failure with joins to unflattened subqueries.	14 years ago
.gitignore	…
COPYRIGHT	…
GNUmakefile.in	…
Makefile	…
README	…
README.git	…
aclocal.m4	…
configure	Add infrastructure for compile-time assertions about variable types.	14 years ago
configure.in	Add infrastructure for compile-time assertions about variable types.	14 years ago

README

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:

	http://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.  Changes between all PostgreSQL releases are recorded in the
file HISTORY.  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
http://www.postgresql.org/download/.  For more information look at our
web site located at http://www.postgresql.org/.