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column with a default expression. In that situation, we need to rewrite the heap relation. To evaluate the new default expression, we use ExecEvalExpr(); however, this can allocate memory in the current memory context, and ATRewriteTable() does not switch out of the active portal's heap memory context. The end result is a rather large memory leak (on the order of gigabytes for a reasonably sized table). This patch changes ATRewriteTable() to switch to the per-tuple memory context before beginning the per-tuple loop. It also removes an explicit heap_freetuple() in the loop, since that is no longer needed. In an unrelated change, I noticed the code was scanning through the attributes of the new tuple descriptor for each tuple of the old table. I changed this to use precomputation, which should slightly speed up the loop. Thanks to steve@deefs.net for reporting the leak.
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. The JDBC, ODBC, C++, Python, and Tcl interfaces have been moved to the PostgreSQL Projects Web Site at http://gborg.postgresql.org for separate maintenance. A Perl DBI/DBD driver is available from CPAN. 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 ftp://ftp.postgresql.org/pub/. For more information look at our web site located at http://www.postgresql.org/.