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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>E.132. Release 9.1.2</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets V1.79.1" /><link rel="prev" href="release-9-1-3.html" title="E.131. Release 9.1.3" /><link rel="next" href="release-9-1-1.html" title="E.133. Release 9.1.1" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">E.132. Release 9.1.2</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="release-9-1-3.html" title="E.131. Release 9.1.3">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="release.html" title="Appendix E. Release Notes">Up</a></td><th width="60%" align="center">Appendix E. Release Notes</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 11.1 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="release-9-1-1.html" title="E.133. Release 9.1.1">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="RELEASE-9-1-2"><div class="titlepage"><div><div><h2 class="title" style="clear: both">E.132. Release 9.1.2</h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="release-9-1-2.html#id-1.11.6.136.4">E.132.1. Migration to Version 9.1.2</a></span></dt><dt><span class="sect2"><a href="release-9-1-2.html#id-1.11.6.136.5">E.132.2. Changes</a></span></dt></dl></div><p><strong>Release date: </strong>2011-12-05</p><p>
   This release contains a variety of fixes from 9.1.1.
   For information about new features in the 9.1 major release, see
   <a class="xref" href="release-9-1.html" title="E.134. Release 9.1">Section E.134</a>.
  </p><div class="sect2" id="id-1.11.6.136.4"><div class="titlepage"><div><div><h3 class="title">E.132.1. Migration to Version 9.1.2</h3></div></div></div><p>
    A dump/restore is not required for those running 9.1.X.
   </p><p>
    However, a longstanding error was discovered in the definition of the
    <code class="literal">information_schema.referential_constraints</code> view.  If you
    rely on correct results from that view, you should replace its
    definition as explained in the first changelog item below.
   </p><p>
    Also, if you use the <code class="type">citext</code> data type, and you upgraded
    from a previous major release by running <span class="application">pg_upgrade</span>,
    you should run <code class="literal">CREATE EXTENSION citext FROM unpackaged</code>
    to avoid collation-related failures in <code class="type">citext</code> operations.
    The same is necessary if you restore a dump from a pre-9.1 database
    that contains an instance of the <code class="type">citext</code> data type.
    If you've already run the <code class="command">CREATE EXTENSION</code> command before
    upgrading to 9.1.2, you will instead need to do manual catalog updates
    as explained in the second changelog item.
   </p></div><div class="sect2" id="id-1.11.6.136.5"><div class="titlepage"><div><div><h3 class="title">E.132.2. Changes</h3></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
      Fix bugs in <code class="literal">information_schema.referential_constraints</code> view
      (Tom Lane)
     </p><p>
      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.
     </p><p>
      Since the view definition is installed by <span class="application">initdb</span>,
      merely upgrading will not fix the problem.  If you need to fix this
      in an existing installation, you can (as a superuser) drop the
      <code class="literal">information_schema</code> schema then re-create it by sourcing
      <code class="filename"><em class="replaceable"><code>SHAREDIR</code></em>/information_schema.sql</code>.
      (Run <code class="literal">pg_config --sharedir</code> if you're uncertain where
      <em class="replaceable"><code>SHAREDIR</code></em> is.)  This must be repeated in each database
      to be fixed.
     </p></li><li class="listitem"><p>
      Make <code class="filename">contrib/citext</code>'s upgrade script fix collations of
      <code class="type">citext</code> columns and indexes (Tom Lane)
     </p><p>
      Existing <code class="type">citext</code> columns and indexes aren't correctly marked as
      being of a collatable data type during <span class="application">pg_upgrade</span> from
      a pre-9.1 server, or when a pre-9.1 dump containing the <code class="type">citext</code>
      type is loaded into a 9.1 server.
      That leads to operations on these columns failing with errors
      such as <span class="quote">“<span class="quote">could not determine which collation to use for string
      comparison</span>”</span>.  This change allows them to be fixed by the same
      script that upgrades the <code class="type">citext</code> module into a proper 9.1
      extension during <code class="literal">CREATE EXTENSION citext FROM unpackaged</code>.
     </p><p>
      If you have a previously-upgraded database that is suffering from this
      problem, and you already ran the <code class="command">CREATE EXTENSION</code> command,
      you can manually run (as superuser) the <code class="command">UPDATE</code> commands
      found at the end of
      <code class="filename"><em class="replaceable"><code>SHAREDIR</code></em>/extension/citext--unpackaged--1.0.sql</code>.
      (Run <code class="literal">pg_config --sharedir</code> if you're uncertain where
      <em class="replaceable"><code>SHAREDIR</code></em> is.)
      There is no harm in doing this again if unsure.
     </p></li><li class="listitem"><p>
      Fix possible crash during <code class="command">UPDATE</code> or <code class="command">DELETE</code> that
      joins to the output of a scalar-returning function (Tom Lane)
     </p><p>
      A crash could only occur if the target row had been concurrently
      updated, so this problem surfaced only intermittently.
     </p></li><li class="listitem"><p>
      Fix incorrect replay of WAL records for GIN index updates
      (Tom Lane)
     </p><p>
      This could result in transiently failing to find index entries after
      a crash, or on a hot-standby server.  The problem would be repaired
      by the next <code class="command">VACUUM</code> of the index, however.
     </p></li><li class="listitem"><p>
      Fix TOAST-related data corruption during <code class="literal">CREATE TABLE dest AS
      SELECT * FROM src</code> or <code class="literal">INSERT INTO dest SELECT * FROM src</code>
      (Tom Lane)
     </p><p>
      If a table has been modified by <code class="command">ALTER TABLE ADD COLUMN</code>,
      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.
     </p></li><li class="listitem"><p>
      Fix possible failures during hot standby startup (Simon Riggs)
     </p></li><li class="listitem"><p>
      Start hot standby faster when initial snapshot is incomplete
      (Simon Riggs)
     </p></li><li class="listitem"><p>
      Fix race condition during toast table access from stale syscache entries
      (Tom Lane)
     </p><p>
      The typical symptom was transient errors like <span class="quote">“<span class="quote">missing chunk
      number 0 for toast value NNNNN in pg_toast_2619</span>”</span>, where the cited
      toast table would always belong to a system catalog.
     </p></li><li class="listitem"><p>
      Track dependencies of functions on items used in parameter default
      expressions (Tom Lane)
     </p><p>
      Previously, a referenced object could be dropped without having dropped
      or modified the function, leading to misbehavior when the function was
      used.  Note that merely installing this update will not fix the missing
      dependency entries; to do that, you'd need to <code class="command">CREATE OR
      REPLACE</code> each such function afterwards.  If you have functions whose
      defaults depend on non-built-in objects, doing so is recommended.
     </p></li><li class="listitem"><p>
      Fix incorrect management of placeholder variables in nestloop joins
      (Tom Lane)
     </p><p>
      This bug is known to lead to <span class="quote">“<span class="quote">variable not found in subplan target
      list</span>”</span> planner errors, and could possibly result in wrong query output
      when outer joins are involved.
     </p></li><li class="listitem"><p>
      Fix window functions that sort by expressions involving aggregates
      (Tom Lane)
     </p><p>
      Previously these could fail with <span class="quote">“<span class="quote">could not find pathkey item to
      sort</span>”</span> planner errors.
     </p></li><li class="listitem"><p>
      Fix <span class="quote">“<span class="quote">MergeAppend child's targetlist doesn't match MergeAppend</span>”</span>
      planner errors (Tom Lane)
     </p></li><li class="listitem"><p>
      Fix index matching for operators with both collatable and noncollatable
      inputs (Tom Lane)
     </p><p>
      In 9.1.0, an indexable operator that has a non-collatable left-hand
      input type and a collatable right-hand input type would not be
      recognized as matching the left-hand column's index.  An example is
      the <code class="type">hstore</code> <code class="literal">?</code> <code class="type">text</code> operator.
     </p></li><li class="listitem"><p>
      Allow inlining of set-returning SQL functions with multiple OUT
      parameters (Tom Lane)
     </p></li><li class="listitem"><p>
      Don't trust deferred-unique indexes for join removal (Tom Lane and Marti
      Raudsepp)
     </p><p>
      A deferred uniqueness constraint might not hold intra-transaction,
      so assuming that it does could give incorrect query results.
     </p></li><li class="listitem"><p>
      Make <code class="function">DatumGetInetP()</code> unpack inet datums that have a 1-byte
      header, and add a new macro, <code class="function">DatumGetInetPP()</code>, that does
      not (Heikki Linnakangas)
     </p><p>
      This change affects no core code, but might prevent crashes in add-on
      code that expects <code class="function">DatumGetInetP()</code> to produce an unpacked
      datum as per usual convention.
     </p></li><li class="listitem"><p>
      Improve locale support in <code class="type">money</code> type's input and output
      (Tom Lane)
     </p><p>
      Aside from not supporting all standard
      <a class="link" href="runtime-config-client.html#GUC-LC-MONETARY"><code class="varname">lc_monetary</code></a>
      formatting options, the input and output functions were inconsistent,
      meaning there were locales in which dumped <code class="type">money</code> values could
      not be re-read.
     </p></li><li class="listitem"><p>
      Don't let <a class="link" href="runtime-config-compatible.html#GUC-TRANSFORM-NULL-EQUALS"><code class="varname">transform_null_equals</code></a>
      affect <code class="literal">CASE foo WHEN NULL ...</code> constructs
      (Heikki Linnakangas)
     </p><p>
      <code class="varname">transform_null_equals</code> is only supposed to affect
      <code class="literal">foo = NULL</code> expressions written directly by the user, not
      equality checks generated internally by this form of <code class="literal">CASE</code>.
     </p></li><li class="listitem"><p>
      Change foreign-key trigger creation order to better support
      self-referential foreign keys (Tom Lane)
     </p><p>
      For a cascading foreign key that references its own table, a row update
      will fire both the <code class="literal">ON UPDATE</code> trigger and the
      <code class="literal">CHECK</code> trigger as one event.  The <code class="literal">ON UPDATE</code>
      trigger must execute first, else the <code class="literal">CHECK</code> 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
      <span class="quote">“<span class="quote">RI_ConstraintTrigger_NNNN</span>”</span>.  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.
     </p></li><li class="listitem"><p>
      Fix <code class="literal">IF EXISTS</code> to work correctly in <code class="command">DROP OPERATOR
      FAMILY</code> (Robert Haas)
     </p></li><li class="listitem"><p>
      Disallow dropping of an extension from within its own script
      (Tom Lane)
     </p><p>
      This prevents odd behavior in case of incorrect management of extension
      dependencies.
     </p></li><li class="listitem"><p>
      Don't mark auto-generated types as extension members (Robert Haas)
     </p><p>
      Relation rowtypes and automatically-generated array types do not need to
      have their own extension membership entries in <code class="structname">pg_depend</code>,
      and creating such entries complicates matters for extension upgrades.
     </p></li><li class="listitem"><p>
      Cope with invalid pre-existing <code class="varname">search_path</code> settings during
      <code class="command">CREATE EXTENSION</code> (Tom Lane)
     </p></li><li class="listitem"><p>
      Avoid floating-point underflow while tracking buffer allocation rate
      (Greg Matthews)
     </p><p>
      While harmless in itself, on certain platforms this would result in
      annoying kernel log messages.
     </p></li><li class="listitem"><p>
      Prevent autovacuum transactions from running in serializable mode
      (Tom Lane)
     </p><p>
      Autovacuum formerly used the cluster-wide default transaction isolation
      level, but there is no need for it to use anything higher than READ
      COMMITTED, and using SERIALIZABLE could result in unnecessary delays
      for other processes.
     </p></li><li class="listitem"><p>
      Ensure walsender processes respond promptly to <span class="systemitem">SIGTERM</span>
      (Magnus Hagander)
     </p></li><li class="listitem"><p>
      Exclude <code class="filename">postmaster.opts</code> from base backups
      (Magnus Hagander)
     </p></li><li class="listitem"><p>
      Preserve configuration file name and line number values when starting
      child processes under Windows (Tom Lane)
     </p><p>
      Formerly, these would not be displayed correctly in the
      <code class="structname">pg_settings</code> view.
     </p></li><li class="listitem"><p>
      Fix incorrect field alignment in <span class="application">ecpg</span>'s SQLDA area
      (Zoltan Boszormenyi)
     </p></li><li class="listitem"><p>
      Preserve blank lines within commands in <span class="application">psql</span>'s command
      history (Robert Haas)
     </p><p>
      The former behavior could cause problems if an empty line was removed
      from within a string literal, for example.
     </p></li><li class="listitem"><p>
      Avoid platform-specific infinite loop in <span class="application">pg_dump</span>
      (Steve Singer)
     </p></li><li class="listitem"><p>
      Fix compression of plain-text output format in <span class="application">pg_dump</span>
      (Adrian Klaver and Tom Lane)
     </p><p>
      <span class="application">pg_dump</span> has historically understood <code class="literal">-Z</code> with
      no <code class="literal">-F</code> switch to mean that it should emit a gzip-compressed
      version of its plain text output.  Restore that behavior.
     </p></li><li class="listitem"><p>
      Fix <span class="application">pg_dump</span> to dump user-defined casts between
      auto-generated types, such as table rowtypes (Tom Lane)
     </p></li><li class="listitem"><p>
      Fix missed quoting of foreign server names in <span class="application">pg_dump</span>
      (Tom Lane)
     </p></li><li class="listitem"><p>
      Assorted fixes for <span class="application">pg_upgrade</span> (Bruce Momjian)
     </p><p>
      Handle exclusion constraints correctly, avoid failures on Windows,
      don't complain about mismatched toast table names in 8.4 databases.
     </p></li><li class="listitem"><p>
      In PL/pgSQL, allow foreign tables to define row types
      (Alexander Soudakov)
     </p></li><li class="listitem"><p>
      Fix up conversions of PL/Perl functions' results
      (Alex Hunsaker and Tom Lane)
     </p><p>
      Restore the pre-9.1 behavior that PL/Perl functions returning
      <code class="type">void</code> ignore the result value of their last Perl statement;
      9.1.0 would throw an error if that statement returned a reference.
      Also, make sure it works to return a string value for a composite type,
      so long as the string meets the type's input format.
      In addition, throw errors for attempts to return Perl arrays or hashes
      when the function's declared result type is not an array or composite
      type, respectively.  (Pre-9.1 versions rather uselessly returned
      strings like <code class="literal">ARRAY(0x221a9a0)</code> or
      <code class="literal">HASH(0x221aa90)</code> in such cases.)
     </p></li><li class="listitem"><p>
      Ensure PL/Perl strings are always correctly UTF8-encoded
      (Amit Khandekar and Alex Hunsaker)
     </p></li><li class="listitem"><p>
      Use the preferred version of <span class="application">xsubpp</span> to build PL/Perl,
      not necessarily the operating system's main copy
      (David Wheeler and Alex Hunsaker)
     </p></li><li class="listitem"><p>
      Correctly propagate SQLSTATE in PL/Python exceptions
      (Mika Eloranta and Jan Urbanski)
     </p></li><li class="listitem"><p>
      Do not install PL/Python extension files for Python major versions
      other than the one built against (Peter Eisentraut)
     </p></li><li class="listitem"><p>
      Change all the <code class="filename">contrib</code> extension script files to report
      a useful error message if they are fed to <span class="application">psql</span>
      (Andrew Dunstan and Tom Lane)
     </p><p>
      This should help teach people about the new method of using
      <code class="command">CREATE EXTENSION</code> to load these files.  In most cases,
      sourcing the scripts directly would fail anyway, but with
      harder-to-interpret messages.
     </p></li><li class="listitem"><p>
      Fix incorrect coding in <code class="filename">contrib/dict_int</code> and
      <code class="filename">contrib/dict_xsyn</code> (Tom Lane)
     </p><p>
      Some functions incorrectly assumed that memory returned by
      <code class="function">palloc()</code> is guaranteed zeroed.
     </p></li><li class="listitem"><p>
      Remove <code class="filename">contrib/sepgsql</code> tests from the regular regression
      test mechanism (Tom Lane)
     </p><p>
      Since these tests require root privileges for setup, they're impractical
      to run automatically.  Switch over to a manual approach instead, and
      provide a testing script to help with that.
     </p></li><li class="listitem"><p>
      Fix assorted errors in <code class="filename">contrib/unaccent</code>'s configuration
      file parsing (Tom Lane)
     </p></li><li class="listitem"><p>
      Honor query cancel interrupts promptly in <code class="function">pgstatindex()</code>
      (Robert Haas)
     </p></li><li class="listitem"><p>
      Fix incorrect quoting of log file name in macOS start script
      (Sidar Lopez)
     </p></li><li class="listitem"><p>
      Revert unintentional enabling of <code class="literal">WAL_DEBUG</code> (Robert Haas)
     </p><p>
      Fortunately, as debugging tools go, this one is pretty cheap;
      but it's not intended to be enabled by default, so revert.
     </p></li><li class="listitem"><p>
      Ensure VPATH builds properly install all server header files
      (Peter Eisentraut)
     </p></li><li class="listitem"><p>
      Shorten file names reported in verbose error messages (Peter Eisentraut)
     </p><p>
      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.
     </p></li><li class="listitem"><p>
      Fix interpretation of Windows timezone names for Central America
      (Tom Lane)
     </p><p>
      Map <span class="quote">“<span class="quote">Central America Standard Time</span>”</span> to <code class="literal">CST6</code>, not
      <code class="literal">CST6CDT</code>, because DST is generally not observed anywhere in
      Central America.
     </p></li><li class="listitem"><p>
      Update time zone data files to <span class="application">tzdata</span> release 2011n
      for DST law changes in Brazil, Cuba, Fiji, Palestine, Russia, and Samoa;
      also historical corrections for Alaska and British East Africa.
     </p></li></ul></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="release-9-1-3.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="release.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="release-9-1-1.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">E.131. Release 9.1.3 </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> E.133. Release 9.1.1</td></tr></table></div></body></html>