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Bruce Momjian 603e153bb8 I don't like last minute patches before the final freeze, but I believe that
this one could be useful for people experiencing out-of-memory crashes while
executing queries which retrieve or use a very large number of tuples.

The problem happens when storage is allocated for functions results used in
a large query, for example:

  select upper(name) from big_table;
  select big_table.array[1] from big_table;
  select count(upper(name)) from big_table;

This patch is a dirty hack that fixes the out-of-memory problem for the most
common cases, like the above ones. It is not the final solution for the
problem but it can work for some people, so I'm posting it.

The patch should be safe because all changes are under #ifdef. Furthermore
the feature can be enabled or disabled at runtime by the `free_tuple_memory'
options in the pg_options file. The option is disabled by default and must
be explicitly enabled at runtime to have any effect.

To enable the patch add the follwing line to Makefile.custom:

CUSTOM_COPT += -DFREE_TUPLE_MEMORY

To enable the option at runtime add the following line to pg_option:

free_tuple_memory=1

Massimo
1999-06-12 14:05:41 +00:00
contrib Update from Massimo 1999-06-05 20:07:54 +00:00
doc More about chained mode and isolation levels. 1999-06-11 05:19:53 +00:00
src I don't like last minute patches before the final freeze, but I believe that 1999-06-12 14:05:41 +00:00
COPYRIGHT
HISTORY
INSTALL
README
register.txt Add mention of new pg_dump feature. 1999-06-08 16:42:10 +00:00

PostgreSQL Data Base Management System (formerly known as Postgres, then
as Postgres95).
  
This directory contains the development version of 6.5 of the PostgreSQL
database server.  The server is not ANSI SQL compliant, but it gets
closer with every release.  After you unzip and untar the distribution
file, look at file INSTALL for the installation notes and file HISTORY
for the changes.

The latest version of this software may be obtained at
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PostgreSQL is not public domain software.  It is copyrighted by the
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POSTGRES95 Data Base Management System (formerly known as Postgres, then
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