doc/src/sgml/ref/pg_dumpall.sgml - master - githubmirror/postgres

doc/src/sgml/ref/pg_dumpall.sgml
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Michael Paquier
doc: Update pg_dump/dumpall/upgrade about handling of external statistics
23 июн 2026, 02:20
23 июн 2026, 02:20f0a4f28
<!--
doc/src/sgml/ref/pg_dumpall.sgml
PostgreSQL documentation
-->

<refentry id="app-pg-dumpall">
 <indexterm zone="app-pg-dumpall">
  <primary>pg_dumpall</primary>
 </indexterm>

 <refmeta>
  <refentrytitle><application>pg_dumpall</application></refentrytitle>
  <manvolnum>1</manvolnum>
  <refmiscinfo>Application</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>pg_dumpall</refname>
  <refpurpose>extract a <productname>PostgreSQL</productname> database cluster into a script file</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
  <cmdsynopsis>
   <command>pg_dumpall</command>
   <arg rep="repeat"><replaceable>connection-option</replaceable></arg>
   <arg rep="repeat"><replaceable>option</replaceable></arg>
  </cmdsynopsis>
 </refsynopsisdiv>

 <refsect1 id="app-pg-dumpall-description">
  <title>Description</title>

  <para>
   <application>pg_dumpall</application> is a utility for writing out
   (<quote>dumping</quote>) all <productname>PostgreSQL</productname> databases
   of a cluster into one script file.  The script file contains
   <acronym>SQL</acronym> commands that can be used as input to <xref
   linkend="app-psql"/> to restore the databases.  It does this by
   calling <xref linkend="app-pgdump"/> for each database in the cluster.
   <application>pg_dumpall</application> also dumps global objects
   that are common to all databases, namely database roles, tablespaces,
   and privilege grants for configuration parameters.
   (<application>pg_dump</application> does not save these objects.)
  </para>

  <para>
   Since <application>pg_dumpall</application> reads tables from all
   databases you will most likely have to connect as a database
   superuser in order to produce a complete dump.  Also you will need
   superuser privileges to execute the saved script in order to be
   allowed to add roles and create databases.
  </para>

  <para>
   The SQL script will be written to the standard output.  Use the
   <option>-f</option>/<option>--file</option> option or shell operators to
   redirect it into a file.
  </para>

  <para>
  <application>pg_dumpall</application> needs to connect several
  times to the <productname>PostgreSQL</productname> server (once per
  database).  If you use password authentication it will ask for
  a password each time. It is convenient to have a
  <filename>~/.pgpass</filename> file in such cases. See <xref
  linkend="libpq-pgpass"/> for more information.
  </para>

  <warning>
   <para>
    Restoring a dump causes the destination to execute arbitrary code of the
    source superusers' choice.  Partial dumps and partial restores do not limit
    that.  If the source superusers are not trusted, the dumped SQL statements
    must be inspected before restoring.  Note that the client running the dump
    and restore need not trust the source or destination superusers.
   </para>
  </warning>

 </refsect1>

 <refsect1>
  <title>Options</title>

   <para>
    The following command-line options control the content and
    format of the output.

    <variablelist>
     <varlistentry>
      <term><option>-a</option></term>
      <term><option>--data-only</option></term>
      <listitem>
       <para>
        Dump only the data, not the schema (data definitions) or statistics.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-c</option></term>
      <term><option>--clean</option></term>
      <listitem>
       <para>
        Emit SQL commands to <command>DROP</command> all the dumped
        databases, roles, and tablespaces before recreating them.
        This option is useful when the restore is to overwrite an existing
        cluster.  If any of the objects do not exist in the destination
        cluster, ignorable error messages will be reported during
        restore, unless <option>--if-exists</option> is also specified.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-E <replaceable class="parameter">encoding</replaceable></option></term>
      <term><option>--encoding=<replaceable class="parameter">encoding</replaceable></option></term>
      <listitem>
       <para>
        Create the dump in the specified character set encoding. By default,
        the dump is created in the database encoding.  (Another way to get the
        same result is to set the <envar>PGCLIENTENCODING</envar> environment
        variable to the desired dump encoding.)
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-f <replaceable class="parameter">filename</replaceable></option></term>
      <term><option>--file=<replaceable class="parameter">filename</replaceable></option></term>
      <listitem>
       <para>
        Send output to the specified file.  If this is omitted, the
        standard output is used.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-g</option></term>
      <term><option>--globals-only</option></term>
      <listitem>
       <para>
        Dump only global objects (roles and tablespaces), no databases.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-O</option></term>
      <term><option>--no-owner</option></term>
      <listitem>
       <para>
        Do not output commands to set
        ownership of objects to match the original database.
        By default, <application>pg_dumpall</application> issues
        <command>ALTER OWNER</command> or
        <command>SET SESSION AUTHORIZATION</command>
        statements to set ownership of created schema elements.
        These statements
        will fail when the script is run unless it is started by a superuser
        (or the same user that owns all of the objects in the script).
        To make a script that can be restored by any user, but will give
        that user ownership of all the objects, specify <option>-O</option>.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-r</option></term>
      <term><option>--roles-only</option></term>
      <listitem>
       <para>
        Dump only roles, no databases or tablespaces.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-s</option></term>
      <term><option>--schema-only</option></term>
      <listitem>
       <para>
        Dump only the object definitions (schema), not data.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-S <replaceable class="parameter">username</replaceable></option></term>
      <term><option>--superuser=<replaceable class="parameter">username</replaceable></option></term>
      <listitem>
       <para>
        Specify the superuser user name to use when disabling triggers.
        This is relevant only if <option>--disable-triggers</option> is used.
        (Usually, it's better to leave this out, and instead start the
        resulting script as superuser.)
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-t</option></term>
      <term><option>--tablespaces-only</option></term>
      <listitem>
       <para>
        Dump only tablespaces, no databases or roles.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-v</option></term>
      <term><option>--verbose</option></term>
      <listitem>
       <para>
        Specifies verbose mode.  This will cause
        <application>pg_dumpall</application> to output start/stop
        times to the dump file, and progress messages to standard error.
        Repeating the option causes additional debug-level messages
        to appear on standard error.
        The option is also passed down to <application>pg_dump</application>.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
       <term><option>-V</option></term>
       <term><option>--version</option></term>
       <listitem>
       <para>
       Print the <application>pg_dumpall</application> version and exit.
       </para>
       </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-x</option></term>
      <term><option>--no-privileges</option></term>
      <term><option>--no-acl</option></term>
      <listitem>
       <para>
        Prevent dumping of access privileges (grant/revoke commands).
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--binary-upgrade</option></term>
      <listitem>
       <para>
        This option is for use by in-place upgrade utilities.  Its use
        for other purposes is not recommended or supported.  The
        behavior of the option may change in future releases without
        notice.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--column-inserts</option></term>
      <term><option>--attribute-inserts</option></term>
      <listitem>
       <para>
        Dump data as <command>INSERT</command> commands with explicit
        column names (<literal>INSERT INTO
        <replaceable>table</replaceable>
        (<replaceable>column</replaceable>, ...) VALUES
        ...</literal>).  This will make restoration very slow; it is mainly
        useful for making dumps that can be loaded into
        non-<productname>PostgreSQL</productname> databases.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--disable-dollar-quoting</option></term>
      <listitem>
       <para>
        This option disables the use of dollar quoting for function bodies,
        and forces them to be quoted using SQL standard string syntax.
       </para>
     </listitem>
    </varlistentry>

     <varlistentry>
      <term><option>--disable-triggers</option></term>
      <listitem>
       <para>
        This option is relevant only when creating a dump with data and without schema.
        It instructs <application>pg_dumpall</application> to include commands
        to temporarily disable triggers on the target tables while
        the data is restored.  Use this if you have referential
        integrity checks or other triggers on the tables that you
        do not want to invoke during data restore.
       </para>

       <para>
        Presently, the commands emitted for <option>--disable-triggers</option>
        must be done as superuser.  So, you should also specify
        a superuser name with <option>-S</option>, or preferably be careful to
        start the resulting script as a superuser.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--exclude-database=<replaceable class="parameter">pattern</replaceable></option></term>
      <listitem>
       <para>
        Do not dump databases whose name matches
        <replaceable class="parameter">pattern</replaceable>.
        Multiple patterns can be excluded by writing multiple
        <option>--exclude-database</option> switches.  The
        <replaceable class="parameter">pattern</replaceable> parameter is
        interpreted as a pattern according to the same rules used by
        <application>psql</application>'s <literal>\d</literal>
        commands (see <xref linkend="app-psql-patterns"/>),
        so multiple databases can also be excluded by writing wildcard
        characters in the pattern.  When using wildcards, be careful to
        quote the pattern if needed to prevent shell wildcard expansion.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--extra-float-digits=<replaceable class="parameter">ndigits</replaceable></option></term>
      <listitem>
       <para>
        Use the specified value of extra_float_digits when dumping
        floating-point data, instead of the maximum available precision.
        Routine dumps made for backup purposes should not use this option.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--filter=<replaceable class="parameter">filename</replaceable></option></term>
      <listitem>
       <para>
        Specify a filename from which to read patterns for databases excluded
        from the dump. The patterns are interpreted according to the same rules
        as <option>--exclude-database</option>.
        To read from <literal>STDIN</literal>, use <filename>-</filename> as the
        filename.  The <option>--filter</option> option can be specified in
        conjunction with <option>--exclude-database</option> for excluding
        databases, and can also be specified more than once for multiple filter
        files.
       </para>

       <para>
        The file lists one database pattern per row, with the following format:
<synopsis>
exclude database <replaceable class="parameter">PATTERN</replaceable>
</synopsis>
       </para>

       <para>
        Lines starting with <literal>#</literal> are considered comments and
        ignored. Comments can be placed after an object pattern row as well.
        Blank lines are also ignored. See <xref linkend="app-psql-patterns"/>
        for how to perform quoting in patterns.
       </para>

      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--if-exists</option></term>
      <listitem>
       <para>
        Use <literal>DROP ... IF EXISTS</literal> commands to drop objects
        in <option>--clean</option> mode.  This suppresses <quote>does not
        exist</quote> errors that might otherwise be reported.  This
        option is not valid unless <option>--clean</option> is also
        specified.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--inserts</option></term>
      <listitem>
       <para>
        Dump data as <command>INSERT</command> commands (rather
        than <command>COPY</command>).  This will make restoration very slow;
        it is mainly useful for making dumps that can be loaded into
        non-<productname>PostgreSQL</productname> databases.  Note that
        the restore might fail altogether if you have rearranged column order.
        The <option>--column-inserts</option> option is safer, though even
        slower.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--load-via-partition-root</option></term>
      <listitem>
       <para>
        When dumping data for a table partition, make
        the <command>COPY</command> or <command>INSERT</command> statements
        target the root of the partitioning hierarchy that contains it, rather
        than the partition itself.  This causes the appropriate partition to
        be re-determined for each row when the data is loaded.  This may be
        useful when restoring data on a server where rows do not always fall
        into the same partitions as they did on the original server.  That
        could happen, for example, if the partitioning column is of type text
        and the two systems have different definitions of the collation used
        to sort the partitioning column.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--lock-wait-timeout=<replaceable class="parameter">timeout</replaceable></option></term>
      <listitem>
       <para>
        Do not wait forever to acquire shared table locks at the beginning of
        the dump. Instead, fail if unable to lock a table within the specified
        <replaceable class="parameter">timeout</replaceable>. The timeout may be
        specified in any of the formats accepted by <command>SET
        statement_timeout</command>.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-comments</option></term>
      <listitem>
       <para>
        Do not dump <command>COMMENT</command> commands.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-data</option></term>
      <listitem>
       <para>
        Do not dump data.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-policies</option></term>
      <listitem>
       <para>
        Do not dump row security policies.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-publications</option></term>
      <listitem>
       <para>
        Do not dump publications.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-role-passwords</option></term>
      <listitem>
       <para>
        Do not dump passwords for roles.  When restored, roles will have a
        null password, and password authentication will always fail until the
        password is set.  Since password values aren't needed when this option
        is specified, the role information is read from the catalog
        view <structname>pg_roles</structname> instead
        of <structname>pg_authid</structname>.  Therefore, this option also
        helps if access to <structname>pg_authid</structname> is restricted by
        some security policy.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-schema</option></term>
      <listitem>
       <para>
        Do not dump schema (data definitions).
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-security-labels</option></term>
      <listitem>
       <para>
        Do not dump security labels.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-statistics</option></term>
      <listitem>
       <para>
        Do not dump statistics. This is the default.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-subscriptions</option></term>
      <listitem>
       <para>
        Do not dump subscriptions.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-sync</option></term>
      <listitem>
       <para>
        By default, <command>pg_dumpall</command> will wait for all files
        to be written safely to disk.  This option causes
        <command>pg_dumpall</command> to return without waiting, which is
        faster, but means that a subsequent operating system crash can leave
        the dump corrupt.  Generally, this option is useful for testing
        but should not be used when dumping data from production installation.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-table-access-method</option></term>
      <listitem>
       <para>
        Do not output commands to select table access methods.
        With this option, all objects will be created with whichever
        table access method is the default during restore.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-tablespaces</option></term>
      <listitem>
       <para>
        Do not output commands to create tablespaces nor select tablespaces
        for objects.
        With this option, all objects will be created in whichever
        tablespace is the default during restore.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-toast-compression</option></term>
      <listitem>
       <para>
        Do not output commands to set <acronym>TOAST</acronym> compression
        methods.
        With this option, all columns will be restored with the default
        compression setting.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--no-unlogged-table-data</option></term>
      <listitem>
       <para>
        Do not dump the contents of unlogged tables.  This option has no
        effect on whether or not the table definitions (schema) are dumped;
        it only suppresses dumping the table data.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--on-conflict-do-nothing</option></term>
      <listitem>
       <para>
        Add <literal>ON CONFLICT DO NOTHING</literal> to
        <command>INSERT</command> commands.
        This option is not valid unless <option>--inserts</option> or
        <option>--column-inserts</option> is also specified.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--quote-all-identifiers</option></term>
      <listitem>
       <para>
        Force quoting of all identifiers.  This option is recommended when
        dumping a database from a server whose <productname>PostgreSQL</productname>
        major version is different from <application>pg_dumpall</application>'s, or when
        the output is intended to be loaded into a server of a different
        major version.  By default, <application>pg_dumpall</application> quotes only
        identifiers that are reserved words in its own major version.
        This sometimes results in compatibility issues when dealing with
        servers of other versions that may have slightly different sets
        of reserved words.  Using <option>--quote-all-identifiers</option> prevents
        such issues, at the price of a harder-to-read dump script.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--restrict-key=<replaceable class="parameter">restrict_key</replaceable></option></term>
      <listitem>
       <para>
        Use the provided string as the <application>psql</application>
        <command>\restrict</command> key in the dump output.  If no restrict
        key is specified, <application>pg_dumpall</application> will generate a
        random one as needed.  Keys may contain only alphanumeric characters.
       </para>
       <para>
        This option is primarily intended for testing purposes and other
        scenarios that require repeatable output (e.g., comparing dump files).
        It is not recommended for general use, as a malicious server with
        advance knowledge of the key may be able to inject arbitrary code that
        will be executed on the machine that runs
        <application>psql</application> with the dump output.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--rows-per-insert=<replaceable class="parameter">nrows</replaceable></option></term>
      <listitem>
       <para>
        Dump data as <command>INSERT</command> commands (rather than
        <command>COPY</command>).  Controls the maximum number of rows per
        <command>INSERT</command> command. The value specified must be a
        number greater than zero.  Any error during restoring will cause only
        rows that are part of the problematic <command>INSERT</command> to be
        lost, rather than the entire table contents.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--statistics</option></term>
      <listitem>
       <para>
        Dump optimizer statistics.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--statistics-only</option></term>
      <listitem>
       <para>
        Dump only the statistics, not the schema (data definitions) or data.
        Optimizer statistics for tables, materialized views, foreign tables,
        and indexes are dumped.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--sequence-data</option></term>
      <listitem>
       <para>
        Include sequence data in the dump.  This is the default behavior except
        when <option>--no-data</option>, <option>--schema-only</option>, or
        <option>--statistics-only</option> is specified.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--use-set-session-authorization</option></term>
      <listitem>
       <para>
        Output SQL-standard <command>SET SESSION AUTHORIZATION</command> commands
        instead of <command>ALTER OWNER</command> commands to determine object
        ownership.  This makes the dump more standards compatible, but
        depending on the history of the objects in the dump, might not restore
        properly.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
       <term><option>-?</option></term>
       <term><option>--help</option></term>
       <listitem>
       <para>
       Show help about <application>pg_dumpall</application> command line
       arguments, and exit.
       </para>
       </listitem>
     </varlistentry>

    </variablelist>
   </para>

  <para>
   The following command-line options control the database connection parameters.

   <variablelist>
     <varlistentry>
      <term><option>-d <replaceable class="parameter">connstr</replaceable></option></term>
      <term><option>--dbname=<replaceable class="parameter">connstr</replaceable></option></term>
      <listitem>
       <para>
        Specifies parameters used to connect to the server, as a <link
        linkend="libpq-connstring">connection string</link>;  these
        will override any conflicting command line options.
       </para>
       <para>
        The option is called <literal>--dbname</literal> for consistency with other
        client applications, but because <application>pg_dumpall</application>
        needs to connect to many databases, the database name in the
        connection string will be ignored.  Use the <literal>-l</literal>
        option to specify the name of the database used for the initial
        connection, which will dump global objects and discover what other
        databases should be dumped.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-h <replaceable>host</replaceable></option></term>
      <term><option>--host=<replaceable>host</replaceable></option></term>
      <listitem>
       <para>
        Specifies the host name of the machine on which the database
        server is running.  If the value begins with a slash, it is
        used as the directory for the Unix domain socket.  The default
        is taken from the <envar>PGHOST</envar> environment variable,
        if set, else a Unix domain socket connection is attempted.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-l <replaceable>dbname</replaceable></option></term>
      <term><option>--database=<replaceable>dbname</replaceable></option></term>
      <listitem>
       <para>
         Specifies the name of the database to connect to for dumping global
         objects and discovering what other databases should be dumped. If
         not specified, the <literal>postgres</literal> database will be used,
         and if that does not exist, <literal>template1</literal> will be used.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-p <replaceable>port</replaceable></option></term>
      <term><option>--port=<replaceable>port</replaceable></option></term>
      <listitem>
       <para>
        Specifies the TCP port or local Unix domain socket file
        extension on which the server is listening for connections.
        Defaults to the <envar>PGPORT</envar> environment variable, if
        set, or a compiled-in default.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-U <replaceable>username</replaceable></option></term>
      <term><option>--username=<replaceable>username</replaceable></option></term>
      <listitem>
       <para>
        User name to connect as.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-w</option></term>
      <term><option>--no-password</option></term>
      <listitem>
       <para>
        Never issue a password prompt.  If the server requires
        password authentication and a password is not available by
        other means such as a <filename>.pgpass</filename> file, the
        connection attempt will fail.  This option can be useful in
        batch jobs and scripts where no user is present to enter a
        password.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-W</option></term>
      <term><option>--password</option></term>
      <listitem>
       <para>
        Force <application>pg_dumpall</application> to prompt for a
        password before connecting to a database.
       </para>

       <para>
        This option is never essential, since
        <application>pg_dumpall</application> will automatically prompt
        for a password if the server demands password authentication.
        However, <application>pg_dumpall</application> will waste a
        connection attempt finding out that the server wants a password.
        In some cases it is worth typing <option>-W</option> to avoid the extra
        connection attempt.
       </para>

       <para>
        Note that the password prompt will occur again for each database
        to be dumped.  Usually, it's better to set up a
        <filename>~/.pgpass</filename> file than to rely on manual password entry.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>--role=<replaceable class="parameter">rolename</replaceable></option></term>
      <listitem>
       <para>
        Specifies a role name to be used to create the dump.
        This option causes <application>pg_dumpall</application> to issue a
        <command>SET ROLE</command> <replaceable class="parameter">rolename</replaceable>
        command after connecting to the database. It is useful when the
        authenticated user (specified by <option>-U</option>) lacks privileges
        needed by <application>pg_dumpall</application>, but can switch to a role with
        the required rights.  Some installations have a policy against
        logging in directly as a superuser, and use of this option allows
        dumps to be made without violating the policy.
       </para>
      </listitem>
     </varlistentry>
   </variablelist>
  </para>
 </refsect1>


 <refsect1>
  <title>Environment</title>

  <variablelist>
   <varlistentry>
    <term><envar>PGHOST</envar></term>
    <term><envar>PGOPTIONS</envar></term>
    <term><envar>PGPORT</envar></term>
    <term><envar>PGUSER</envar></term>

    <listitem>
     <para>
      Default connection parameters
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><envar>PG_COLOR</envar></term>
    <listitem>
     <para>
      Specifies whether to use color in diagnostic messages. Possible values
      are <literal>always</literal>, <literal>auto</literal> and
      <literal>never</literal>.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>

  <para>
   This utility, like most other <productname>PostgreSQL</productname> utilities,
   also uses the environment variables supported by <application>libpq</application>
   (see <xref linkend="libpq-envars"/>).
  </para>

 </refsect1>


 <refsect1>
  <title>Notes</title>

  <para>
   Since <application>pg_dumpall</application> calls
   <application>pg_dump</application> internally, some diagnostic
   messages will refer to <application>pg_dump</application>.
  </para>

  <para>
   The <option>--clean</option> option can be useful even when your
   intention is to restore the dump script into a fresh cluster.  Use of
   <option>--clean</option> authorizes the script to drop and re-create the
   built-in <literal>postgres</literal> and <literal>template1</literal>
   databases, ensuring that those databases will retain the same properties
   (for instance, locale and encoding) that they had in the source cluster.
   Without the option, those databases will retain their existing
   database-level properties, as well as any pre-existing contents.
  </para>

  <para>
   When <option>--statistics</option> is specified,
   <command>pg_dumpall</command> will include most optimizer statistics in the
   resulting dump file. This does not include all statistics, such as
   custom statistics added by an extension, or statistics collected by the
   cumulative statistics system.  Therefore, it may still be useful to
   run <command>ANALYZE</command> on each database after restoring from a dump
   file to ensure optimal performance.  You can also run <command>vacuumdb -a
   -z</command> to analyze all databases.
  </para>

  <para>
   The dump script should not be expected to run completely without errors.
   In particular, because the script will issue <command>CREATE ROLE</command>
   for every role existing in the source cluster, it is certain to get a
   <quote>role already exists</quote> error for the bootstrap superuser,
   unless the destination cluster was initialized with a different bootstrap
   superuser name.  This error is harmless and should be ignored.  Use of
   the <option>--clean</option> option is likely to produce additional
   harmless error messages about non-existent objects, although you can
   minimize those by adding <option>--if-exists</option>.
  </para>

  <para>
   <application>pg_dumpall</application> requires all needed
   tablespace directories to exist before the restore;  otherwise,
   database creation will fail for databases in non-default
   locations.
  </para>

  <para>
   It is generally recommended to use the <option>-X</option>
   (<option>--no-psqlrc</option>) option when restoring a database from a
   <application>pg_dumpall</application> script to ensure a clean restore
   process and prevent potential conflicts with non-default
   <application>psql</application> configurations. Additionally, because
   the <application>pg_dumpall</application> script may
   include <application>psql</application> meta-commands, it may be
   incompatible with clients other than <application>psql</application>.
  </para>
 </refsect1>


 <refsect1 id="app-pg-dumpall-ex">
  <title>Examples</title>
  <para>
   To dump all databases:

<screen>
<prompt>$</prompt> <userinput>pg_dumpall &gt; db.out</userinput>
</screen>
  </para>

  <para>
   To restore database(s) from this file, you can use:
<screen>
<prompt>$</prompt> <userinput>psql -X -f db.out -d postgres</userinput>
</screen>
   It is not important which database you connect to here since the
   script file created by <application>pg_dumpall</application> will
   contain the appropriate commands to create and connect to the saved
   databases.  An exception is that if you specified <option>--clean</option>,
   you must connect to the <literal>postgres</literal> database initially;
   the script will attempt to drop other databases immediately, and that
   will fail for the database you are connected to.
  </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <para>
    Check <xref linkend="app-pgdump"/> for details on possible
    error conditions.
  </para>
 </refsect1>

</refentry>