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<sect1 id="release-8-2-23">

<title>Release 8.2.23</title>

<note>

<title>Release Date</title>

<simpara>2011-12-05</simpara>

</note>

<para>

This release contains a variety of fixes from 8.2.22.

For information about new features in the 8.2 major release, see

<xref linkend="release-8-2">.

</para>

<para>

This is expected to be the last <productname>PostgreSQL</> release

in the 8.2.X series. Users are encouraged to update to a newer

release branch soon.

</para>

<sect2>

<title>Migration to Version 8.2.23</title>

<para>

A dump/restore is not required for those running 8.2.X.

</para>

<para>

However, a longstanding error was discovered in the definition of the

<literal>information_schema.referential_constraints</> view. If you

rely on correct results from that view, you should replace its

definition as explained in the first changelog item below.

</para>

<para>

Also, if you are upgrading from a version earlier than 8.2.14,

see the release notes for 8.2.14.

</para>

</sect2>

<sect2>

<title>Changes</title>

<itemizedlist>

<listitem>

<para>

Fix bugs in <literal>information_schema.referential_constraints</> view

(Tom Lane)

</para>

<para>

This view was being insufficiently careful about matching the

foreign-key constraint to the depended-on primary or unique key

constraint. That could result in failure to show a foreign key

constraint at all, or showing it multiple times, or claiming that it

depends on a different constraint than the one it really does.

</para>

<para>

Since the view definition is installed by <application>initdb</>,

merely upgrading will not fix the problem. If you need to fix this

in an existing installation, you can (as a superuser) drop the

<literal>information_schema</> schema then re-create it by sourcing

<filename><replaceable>SHAREDIR</>/information_schema.sql</filename>.

(Run <literal>pg_config --sharedir</> if you're uncertain where

<replaceable>SHAREDIR</> is.) This must be repeated in each database

to be fixed.

</para>

</listitem>

<listitem>

<para>

Fix TOAST-related data corruption during <literal>CREATE TABLE dest AS

SELECT * FROM src</> or <literal>INSERT INTO dest SELECT * FROM src</>

(Tom Lane)

</para>

<para>

If a table has been modified by <command>ALTER TABLE ADD COLUMN</>,

attempts to copy its data verbatim to another table could produce

corrupt results in certain corner cases.

The problem can only manifest in this precise form in 8.4 and later,

but we patched earlier versions as well in case there are other code

paths that could trigger the same bug.

</para>

</listitem>

<listitem>

<para>

Fix race condition during toast table access from stale syscache entries

(Tom Lane)

</para>

<para>

The typical symptom was transient errors like <quote>missing chunk

number 0 for toast value NNNNN in pg_toast_2619</>, where the cited

toast table would always belong to a system catalog.

</para>

</listitem>

<listitem>

<para>

Improve locale support in <type>money</> type's input and output

(Tom Lane)

</para>

<para>

Aside from not supporting all standard

<link linkend="guc-lc-monetary"><varname>lc_monetary</></link>

formatting options, the input and output functions were inconsistent,

meaning there were locales in which dumped <type>money</> values could

not be re-read.

</para>

</listitem>

<listitem>

<para>

Don't let <link

linkend="guc-transform-null-equals"><varname>transform_null_equals</></link>

affect <literal>CASE foo WHEN NULL ...</> constructs

(Heikki Linnakangas)

</para>

<para>

<varname>transform_null_equals</> is only supposed to affect

<literal>foo = NULL</> expressions written directly by the user, not

equality checks generated internally by this form of <literal>CASE</>.

</para>

</listitem>

<listitem>

<para>

Change foreign-key trigger creation order to better support

self-referential foreign keys (Tom Lane)

</para>

<para>

For a cascading foreign key that references its own table, a row update

will fire both the <literal>ON UPDATE</> trigger and the

<literal>CHECK</> trigger as one event. The <literal>ON UPDATE</>

trigger must execute first, else the <literal>CHECK</> will check a

non-final state of the row and possibly throw an inappropriate error.

However, the firing order of these triggers is determined by their

names, which generally sort in creation order since the triggers have

auto-generated names following the convention

<quote>RI_ConstraintTrigger_NNNN</>. A proper fix would require

modifying that convention, which we will do in 9.2, but it seems risky

to change it in existing releases. So this patch just changes the

creation order of the triggers. Users encountering this type of error

should drop and re-create the foreign key constraint to get its

triggers into the right order.

</para>

</listitem>

<listitem>

<para>

Preserve blank lines within commands in <application>psql</>'s command

history (Robert Haas)

</para>

<para>

The former behavior could cause problems if an empty line was removed

from within a string literal, for example.

</para>

</listitem>

<listitem>

<para>

Use the preferred version of <application>xsubpp</> to build PL/Perl,

not necessarily the operating system's main copy

(David Wheeler and Alex Hunsaker)

</para>

</listitem>

<listitem>

<para>

Honor query cancel interrupts promptly in <function>pgstatindex()</>

(Robert Haas)

</para>

</listitem>

<listitem>

<para>

Ensure VPATH builds properly install all server header files

(Peter Eisentraut)

</para>

</listitem>

<listitem>

<para>

Shorten file names reported in verbose error messages (Peter Eisentraut)

</para>

<para>

Regular builds have always reported just the name of the C file

containing the error message call, but VPATH builds formerly

reported an absolute path name.

</para>

</listitem>

<listitem>

<para>

Fix interpretation of Windows timezone names for Central America

(Tom Lane)

</para>

<para>

Map <quote>Central America Standard Time</> to <literal>CST6</>, not

<literal>CST6CDT</>, because DST is generally not observed anywhere in

Central America.

</para>

</listitem>

<listitem>

<para>

Update time zone data files to <application>tzdata</> release 2011n

for DST law changes in Brazil, Cuba, Fiji, Palestine, Russia, and Samoa;

also historical corrections for Alaska and British East Africa.

</para>

</listitem>

</itemizedlist>

</sect2>

</sect1>

<sect1 id="release-8-2-22">

<title>Release 8.2.22</title>