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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!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>pg_dump</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="app-pgconfig.html" title="pg_config" /><link rel="next" href="app-pg-dumpall.html" title="pg_dumpall" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center"><span class="application">pg_dump</span></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="app-pgconfig.html" title="pg_config">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="reference-client.html" title="PostgreSQL Client Applications">Up</a></td><th width="60%" align="center">PostgreSQL Client Applications</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="app-pg-dumpall.html" title="pg_dumpall">Next</a></td></tr></table><hr /></div><div class="refentry" id="APP-PGDUMP"><div class="titlepage"></div><a id="id-1.9.4.13.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle"><span class="application">pg_dump</span></span></h2><p>pg_dump — 
   extract a <span class="productname">PostgreSQL</span> database into a script file or other archive file
  </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="cmdsynopsis"><p id="id-1.9.4.13.4.1"><code class="command">pg_dump</code> [<em class="replaceable"><code>connection-option</code></em>...] [<em class="replaceable"><code>option</code></em>...] [<em class="replaceable"><code>dbname</code></em>]</p></div></div><div class="refsect1" id="PG-DUMP-DESCRIPTION"><h2>Description</h2><p>
   <span class="application">pg_dump</span> is a utility for backing up a
   <span class="productname">PostgreSQL</span> database. It makes consistent
   backups even if the database is being used concurrently.
   <span class="application">pg_dump</span> does not block other users
   accessing the database (readers or writers).
  </p><p>
   <span class="application">pg_dump</span> only dumps a single database.
   To back up an entire cluster, or to back up global objects that are
   common to all databases in a cluster (such as roles and tablespaces),
   use <a class="xref" href="app-pg-dumpall.html" title="pg_dumpall"><span class="refentrytitle"><span class="application">pg_dumpall</span></span></a>.
  </p><p>
   Dumps can be output in script or archive file formats. Script
   dumps are plain-text files containing the SQL commands required
   to reconstruct the database to the state it was in at the time it was
   saved. To restore from such a script, feed it to <a class="xref" href="app-psql.html" title="psql"><span class="refentrytitle"><span class="application">psql</span></span></a>. Script files
   can be used to reconstruct the database even on other machines and
   other architectures; with some modifications, even on other SQL
   database products.
  </p><p>
   The alternative archive file formats must be used with
   <a class="xref" href="app-pgrestore.html" title="pg_restore"><span class="refentrytitle"><span class="application">pg_restore</span></span></a> to rebuild the database.  They
   allow <span class="application">pg_restore</span> to be selective about
   what is restored, or even to reorder the items prior to being
   restored.
   The archive file formats are designed to be portable across
   architectures.
  </p><p>
   When used with one of the archive file formats and combined with
   <span class="application">pg_restore</span>,
   <span class="application">pg_dump</span> provides a flexible archival and
   transfer mechanism. <span class="application">pg_dump</span> can be used to
   backup an entire database, then <span class="application">pg_restore</span>
   can be used to examine the archive and/or select which parts of the
   database are to be restored. The most flexible output file formats are
   the <span class="quote"><span class="quote">custom</span></span> format (<code class="option">-Fc</code>) and the
   <span class="quote"><span class="quote">directory</span></span> format (<code class="option">-Fd</code>). They allow
   for selection and reordering of all archived items, support parallel
   restoration, and are compressed by default. The <span class="quote"><span class="quote">directory</span></span>
   format is the only format that supports parallel dumps.
  </p><p>
   While running <span class="application">pg_dump</span>, one should examine the
   output for any warnings (printed on standard error), especially in
   light of the limitations listed below.
  </p></div><div class="refsect1" id="PG-DUMP-OPTIONS"><h2>Options</h2><p>
    The following command-line options control the content and
    format of the output.

    </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>dbname</code></em></span></dt><dd><p>
        Specifies the name of the database to be dumped.  If this is
        not specified, the environment variable
        <code class="envar">PGDATABASE</code> is used.  If that is not set, the
        user name specified for the connection is used.
       </p></dd><dt><span class="term"><code class="option">-a</code><br /></span><span class="term"><code class="option">--data-only</code></span></dt><dd><p>
        Dump only the data, not the schema (data definitions).
        Table data, large objects, and sequence values are dumped.
       </p><p>
        This option is similar to, but for historical reasons not identical
        to, specifying <code class="option">--section=data</code>.
       </p></dd><dt><span class="term"><code class="option">-b</code><br /></span><span class="term"><code class="option">--blobs</code></span></dt><dd><p>
        Include large objects in the dump.  This is the default behavior
        except when <code class="option">--schema</code>, <code class="option">--table</code>, or
        <code class="option">--schema-only</code> is specified.  The <code class="option">-b</code>
        switch is therefore only useful to add large objects to dumps
        where a specific schema or table has been requested.  Note that
        blobs are considered data and therefore will be included when
        <code class="option">--data-only</code> is used, but not
        when <code class="option">--schema-only</code> is.
       </p></dd><dt><span class="term"><code class="option">-B</code><br /></span><span class="term"><code class="option">--no-blobs</code></span></dt><dd><p>
        Exclude large objects in the dump.
       </p><p>
        When both <code class="option">-b</code> and <code class="option">-B</code> are given, the behavior
        is to output large objects, when data is being dumped, see the
        <code class="option">-b</code> documentation.
       </p></dd><dt><span class="term"><code class="option">-c</code><br /></span><span class="term"><code class="option">--clean</code></span></dt><dd><p>
        Output commands to <code class="command">DROP</code> all the dumped
        database objects prior to outputting the commands for creating them.
        This option is useful when the restore is to overwrite an existing
        database.  If any of the objects do not exist in the destination
        database, ignorable error messages will be reported during
        restore, unless <code class="option">--if-exists</code> is also specified.
       </p><p>
        This option is ignored when emitting an archive (non-text) output
        file.  For the archive formats, you can specify the option when you
        call <code class="command">pg_restore</code>.
       </p></dd><dt><span class="term"><code class="option">-C</code><br /></span><span class="term"><code class="option">--create</code></span></dt><dd><p>
        Begin the output with a command to create the
        database itself and reconnect to the created database.  (With a
        script of this form, it doesn't matter which database in the
        destination installation you connect to before running the script.)
        If <code class="option">--clean</code> is also specified, the script drops and
        recreates the target database before reconnecting to it.
       </p><p>
        With <code class="option">--create</code>, the output also includes the
        database's comment if any, and any configuration variable settings
        that are specific to this database, that is,
        any <code class="command">ALTER DATABASE ... SET ...</code>
        and <code class="command">ALTER ROLE ... IN DATABASE ... SET ...</code>
        commands that mention this database.
        Access privileges for the database itself are also dumped,
        unless <code class="option">--no-acl</code> is specified.
       </p><p>
        This option is ignored when emitting an archive (non-text) output
        file.  For the archive formats, you can specify the option when you
        call <code class="command">pg_restore</code>.
       </p></dd><dt><span class="term"><code class="option">-e <em class="replaceable"><code>pattern</code></em></code><br /></span><span class="term"><code class="option">--extension=<em class="replaceable"><code>pattern</code></em></code></span></dt><dd><p>
        Dump only extensions matching <em class="replaceable"><code>pattern</code></em>.  When this option is not
        specified, all non-system extensions in the target database will be
        dumped.  Multiple extensions can be selected by writing multiple
        <code class="option">-e</code> switches.  The <em class="replaceable"><code>pattern</code></em> parameter is interpreted as a
        pattern according to the same rules used by
        <span class="application">psql</span>'s <code class="literal">\d</code> commands (see
        <a class="xref" href="app-psql.html#APP-PSQL-PATTERNS" title="Patterns">Patterns</a>), so multiple extensions can also
        be selected by writing wildcard characters in the pattern.  When using
        wildcards, be careful to quote the pattern if needed to prevent the
        shell from expanding the wildcards.
       </p><p>
        Any configuration relation registered by
        <code class="function">pg_extension_config_dump</code> is included in the
        dump if its extension is specified by <code class="option">--extension</code>.
       </p><div class="note"><h3 class="title">Note</h3><p>
         When <code class="option">-e</code> is specified,
         <span class="application">pg_dump</span> makes no attempt to dump any other
         database objects that the selected extension(s) might depend upon.
         Therefore, there is no guarantee that the results of a
         specific-extension dump can be successfully restored by themselves
         into a clean database.
        </p></div></dd><dt><span class="term"><code class="option">-E <em class="replaceable"><code>encoding</code></em></code><br /></span><span class="term"><code class="option">--encoding=<em class="replaceable"><code>encoding</code></em></code></span></dt><dd><p>
        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 <code class="envar">PGCLIENTENCODING</code> environment
        variable to the desired dump encoding.)  The supported encodings are
        described in <a class="xref" href="multibyte.html#MULTIBYTE-CHARSET-SUPPORTED" title="24.3.1. Supported Character Sets">Section 24.3.1</a>.
       </p></dd><dt><span class="term"><code class="option">-f <em class="replaceable"><code>file</code></em></code><br /></span><span class="term"><code class="option">--file=<em class="replaceable"><code>file</code></em></code></span></dt><dd><p>
        Send output to the specified file. This parameter can be omitted for
        file based output formats, in which case the standard output is used.
        It must be given for the directory output format however, where it
        specifies the target directory instead of a file. In this case the
        directory is created by <code class="command">pg_dump</code> and must not exist
        before.
       </p></dd><dt><span class="term"><code class="option">-F <em class="replaceable"><code>format</code></em></code><br /></span><span class="term"><code class="option">--format=<em class="replaceable"><code>format</code></em></code></span></dt><dd><p>
        Selects the format of the output.
        <em class="replaceable"><code>format</code></em> can be one of the following:

       </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">p</code><br /></span><span class="term"><code class="literal">plain</code></span></dt><dd><p>
           Output a plain-text <acronym class="acronym">SQL</acronym> script file (the default).
          </p></dd><dt><span class="term"><code class="literal">c</code><br /></span><span class="term"><code class="literal">custom</code></span></dt><dd><p>
           Output a custom-format archive suitable for input into
           <span class="application">pg_restore</span>.
           Together with the directory output format, this is the most flexible
           output format in that it allows manual selection and reordering of
           archived items during restore. This format is also compressed by
           default.
          </p></dd><dt><span class="term"><code class="literal">d</code><br /></span><span class="term"><code class="literal">directory</code></span></dt><dd><p>
           Output a directory-format archive suitable for input into
           <span class="application">pg_restore</span>. This will create a directory
           with one file for each table and blob being dumped, plus a
           so-called Table of Contents file describing the dumped objects in a
           machine-readable format that <span class="application">pg_restore</span>
           can read. A directory format archive can be manipulated with
           standard Unix tools; for example, files in an uncompressed archive
           can be compressed with the <span class="application">gzip</span> tool.
           This format is compressed by default and also supports parallel
           dumps.
          </p></dd><dt><span class="term"><code class="literal">t</code><br /></span><span class="term"><code class="literal">tar</code></span></dt><dd><p>
           Output a <code class="command">tar</code>-format archive suitable for input
           into <span class="application">pg_restore</span>. The tar format is
           compatible with the directory format: extracting a tar-format
           archive produces a valid directory-format archive.
           However, the tar format does not support compression. Also, when
           using tar format the relative order of table data items cannot be
           changed during restore.
          </p></dd></dl></div></dd><dt><span class="term"><code class="option">-j <em class="replaceable"><code>njobs</code></em></code><br /></span><span class="term"><code class="option">--jobs=<em class="replaceable"><code>njobs</code></em></code></span></dt><dd><p>
        Run the dump in parallel by dumping <em class="replaceable"><code>njobs</code></em>
        tables simultaneously. This option may reduce the time needed to perform the dump but it also
        increases the load on the database server. You can only use this option with the
        directory output format because this is the only output format where multiple processes
        can write their data at the same time.
       </p><p><span class="application">pg_dump</span> will open <em class="replaceable"><code>njobs</code></em>
        + 1 connections to the database, so make sure your <a class="xref" href="runtime-config-connection.html#GUC-MAX-CONNECTIONS">max_connections</a>
        setting is high enough to accommodate all connections.
       </p><p>
        Requesting exclusive locks on database objects while running a parallel dump could
        cause the dump to fail. The reason is that the <span class="application">pg_dump</span> leader process
        requests shared locks (<a class="link" href="explicit-locking.html#LOCKING-TABLES" title="13.3.1. Table-Level Locks">ACCESS SHARE</a>) on the
        objects that the worker processes are going to dump later in order to
        make sure that nobody deletes them and makes them go away while the dump is running.
        If another client then requests an exclusive lock on a table, that lock will not be
        granted but will be queued waiting for the shared lock of the leader process to be
        released. Consequently any other access to the table will not be granted either and
        will queue after the exclusive lock request. This includes the worker process trying
        to dump the table. Without any precautions this would be a classic deadlock situation.
        To detect this conflict, the <span class="application">pg_dump</span> worker process requests another
        shared lock using the <code class="literal">NOWAIT</code> option. If the worker process is not granted
        this shared lock, somebody else must have requested an exclusive lock in the meantime
        and there is no way to continue with the dump, so <span class="application">pg_dump</span> has no choice
        but to abort the dump.
       </p><p>
        To perform a parallel dump, the database server needs to support
        synchronized snapshots, a feature that was introduced in
        <span class="productname">PostgreSQL</span> 9.2 for primary servers and 10
        for standbys. With this feature, database clients can ensure they see
        the same data set even though they use different connections.
        <code class="command">pg_dump -j</code> uses multiple database connections; it
        connects to the database once with the leader process and once again
        for each worker job. Without the synchronized snapshot feature, the
        different worker jobs wouldn't be guaranteed to see the same data in
        each connection, which could lead to an inconsistent backup.
       </p></dd><dt><span class="term"><code class="option">-n <em class="replaceable"><code>pattern</code></em></code><br /></span><span class="term"><code class="option">--schema=<em class="replaceable"><code>pattern</code></em></code></span></dt><dd><p>
        Dump only schemas matching <em class="replaceable"><code>pattern</code></em>; this selects both the
        schema itself, and all its contained objects.  When this option is
        not specified, all non-system schemas in the target database will be
        dumped.  Multiple schemas can be
        selected by writing multiple <code class="option">-n</code> switches.  The
        <em class="replaceable"><code>pattern</code></em> parameter is
        interpreted as a pattern according to the same rules used by
        <span class="application">psql</span>'s <code class="literal">\d</code> commands
        (see <a class="xref" href="app-psql.html#APP-PSQL-PATTERNS" title="Patterns">Patterns</a> below),
        so multiple schemas can also be selected by writing wildcard characters
        in the pattern.  When using wildcards, be careful to quote the pattern
        if needed to prevent the shell from expanding the wildcards;  see
        <a class="xref" href="app-pgdump.html#PG-DUMP-EXAMPLES" title="Examples">Examples</a> below.
       </p><div class="note"><h3 class="title">Note</h3><p>
         When <code class="option">-n</code> is specified, <span class="application">pg_dump</span>
         makes no attempt to dump any other database objects that the selected
         schema(s) might depend upon. Therefore, there is no guarantee
         that the results of a specific-schema dump can be successfully
         restored by themselves into a clean database.
        </p></div><div class="note"><h3 class="title">Note</h3><p>
         Non-schema objects such as blobs are not dumped when <code class="option">-n</code> is
         specified.  You can add blobs back to the dump with the
         <code class="option">--blobs</code> switch.
        </p></div></dd><dt><span class="term"><code class="option">-N <em class="replaceable"><code>pattern</code></em></code><br /></span><span class="term"><code class="option">--exclude-schema=<em class="replaceable"><code>pattern</code></em></code></span></dt><dd><p>
        Do not dump any schemas matching <em class="replaceable"><code>pattern</code></em>.  The pattern is
        interpreted according to the same rules as for <code class="option">-n</code>.
        <code class="option">-N</code> can be given more than once to exclude schemas
        matching any of several patterns.
       </p><p>
        When both <code class="option">-n</code> and <code class="option">-N</code> are given, the behavior
        is to dump just the schemas that match at least one <code class="option">-n</code>
        switch but no <code class="option">-N</code> switches.  If <code class="option">-N</code> appears
        without <code class="option">-n</code>, then schemas matching <code class="option">-N</code> are
        excluded from what is otherwise a normal dump.
       </p></dd><dt><span class="term"><code class="option">-O</code><br /></span><span class="term"><code class="option">--no-owner</code></span></dt><dd><p>
        Do not output commands to set
        ownership of objects to match the original database.
        By default, <span class="application">pg_dump</span> issues
        <code class="command">ALTER OWNER</code> or
        <code class="command">SET SESSION AUTHORIZATION</code>
        statements to set ownership of created database objects.
        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 <code class="option">-O</code>.
       </p><p>
        This option is ignored when emitting an archive (non-text) output
        file.  For the archive formats, you can specify the option when you
        call <code class="command">pg_restore</code>.
       </p></dd><dt><span class="term"><code class="option">-R</code><br /></span><span class="term"><code class="option">--no-reconnect</code></span></dt><dd><p>
        This option is obsolete but still accepted for backwards
        compatibility.
       </p></dd><dt><span class="term"><code class="option">-s</code><br /></span><span class="term"><code class="option">--schema-only</code></span></dt><dd><p>
        Dump only the object definitions (schema), not data.
       </p><p>
        This option is the inverse of <code class="option">--data-only</code>.
        It is similar to, but for historical reasons not identical to,
        specifying
        <code class="option">--section=pre-data --section=post-data</code>.
       </p><p>
        (Do not confuse this with the <code class="option">--schema</code> option, which
        uses the word <span class="quote"><span class="quote">schema</span></span> in a different meaning.)
       </p><p>
        To exclude table data for only a subset of tables in the database,
        see <code class="option">--exclude-table-data</code>.
       </p></dd><dt><span class="term"><code class="option">-S <em class="replaceable"><code>username</code></em></code><br /></span><span class="term"><code class="option">--superuser=<em class="replaceable"><code>username</code></em></code></span></dt><dd><p>
        Specify the superuser user name to use when disabling triggers.
        This is relevant only if <code class="option">--disable-triggers</code> is used.
        (Usually, it's better to leave this out, and instead start the
        resulting script as superuser.)
       </p></dd><dt><span class="term"><code class="option">-t <em class="replaceable"><code>pattern</code></em></code><br /></span><span class="term"><code class="option">--table=<em class="replaceable"><code>pattern</code></em></code></span></dt><dd><p>
        Dump only tables with names matching
        <em class="replaceable"><code>pattern</code></em>. Multiple tables
        can be selected by writing multiple <code class="option">-t</code> switches.  The
        <em class="replaceable"><code>pattern</code></em> parameter is
        interpreted as a pattern according to the same rules used by
        <span class="application">psql</span>'s <code class="literal">\d</code> commands
        (see <a class="xref" href="app-psql.html#APP-PSQL-PATTERNS" title="Patterns">Patterns</a> below),
        so multiple tables can also be selected by writing wildcard characters
        in the pattern.  When using wildcards, be careful to quote the pattern
        if needed to prevent the shell from expanding the wildcards;  see
        <a class="xref" href="app-pgdump.html#PG-DUMP-EXAMPLES" title="Examples">Examples</a> below.
       </p><p>
        As well as tables, this option can be used to dump the definition of matching
        views, materialized views, foreign tables, and sequences.  It will not dump the
        contents of views or materialized views, and the contents of foreign tables will
        only be dumped if the corresponding foreign server is specified with
        <code class="option">--include-foreign-data</code>.
       </p><p>
        The <code class="option">-n</code> and <code class="option">-N</code> switches have no effect when
        <code class="option">-t</code> is used, because tables selected by <code class="option">-t</code> will
        be dumped regardless of those switches, and non-table objects will not
        be dumped.
       </p><div class="note"><h3 class="title">Note</h3><p>
         When <code class="option">-t</code> is specified, <span class="application">pg_dump</span>
         makes no attempt to dump any other database objects that the selected
         table(s) might depend upon. Therefore, there is no guarantee
         that the results of a specific-table dump can be successfully
         restored by themselves into a clean database.
        </p></div></dd><dt><span class="term"><code class="option">-T <em class="replaceable"><code>pattern</code></em></code><br /></span><span class="term"><code class="option">--exclude-table=<em class="replaceable"><code>pattern</code></em></code></span></dt><dd><p>
        Do not dump any tables matching <em class="replaceable"><code>pattern</code></em>.  The pattern is
        interpreted according to the same rules as for <code class="option">-t</code>.
        <code class="option">-T</code> can be given more than once to exclude tables
        matching any of several patterns.
       </p><p>
        When both <code class="option">-t</code> and <code class="option">-T</code> are given, the behavior
        is to dump just the tables that match at least one <code class="option">-t</code>
        switch but no <code class="option">-T</code> switches.  If <code class="option">-T</code> appears
        without <code class="option">-t</code>, then tables matching <code class="option">-T</code> are
        excluded from what is otherwise a normal dump.
       </p></dd><dt><span class="term"><code class="option">-v</code><br /></span><span class="term"><code class="option">--verbose</code></span></dt><dd><p>
        Specifies verbose mode.  This will cause
        <span class="application">pg_dump</span> to output detailed object
        comments and 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.
       </p></dd><dt><span class="term"><code class="option">-V</code><br /></span><span class="term"><code class="option">--version</code></span></dt><dd><p>
       Print the <span class="application">pg_dump</span> version and exit.
       </p></dd><dt><span class="term"><code class="option">-x</code><br /></span><span class="term"><code class="option">--no-privileges</code><br /></span><span class="term"><code class="option">--no-acl</code></span></dt><dd><p>
        Prevent dumping of access privileges (grant/revoke commands).
       </p></dd><dt><span class="term"><code class="option">-Z <em class="replaceable"><code>0..9</code></em></code><br /></span><span class="term"><code class="option">--compress=<em class="replaceable"><code>0..9</code></em></code></span></dt><dd><p>
        Specify the compression level to use.  Zero means no compression.
        For the custom and directory archive formats, this specifies compression of
        individual table-data segments, and the default is to compress
        at a moderate level.
        For plain text output, setting a nonzero compression level causes
        the entire output file to be compressed, as though it had been
        fed through <span class="application">gzip</span>; but the default is not to compress.
        The tar archive format currently does not support compression at all.
       </p></dd><dt><span class="term"><code class="option">--binary-upgrade</code></span></dt><dd><p>
        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.
       </p></dd><dt><span class="term"><code class="option">--column-inserts</code><br /></span><span class="term"><code class="option">--attribute-inserts</code></span></dt><dd><p>
        Dump data as <code class="command">INSERT</code> commands with explicit
        column names (<code class="literal">INSERT INTO
        <em class="replaceable"><code>table</code></em>
        (<em class="replaceable"><code>column</code></em>, ...) VALUES
        ...</code>).  This will make restoration very slow; it is mainly
        useful for making dumps that can be loaded into
        non-<span class="productname">PostgreSQL</span> databases.
        Any error during restoring will cause only rows that are part of the
        problematic <code class="command">INSERT</code> to be lost, rather than the
        entire table contents.
       </p></dd><dt><span class="term"><code class="option">--disable-dollar-quoting</code></span></dt><dd><p>
        This option disables the use of dollar quoting for function bodies,
        and forces them to be quoted using SQL standard string syntax.
       </p></dd><dt><span class="term"><code class="option">--disable-triggers</code></span></dt><dd><p>
        This option is relevant only when creating a data-only dump.
        It instructs <span class="application">pg_dump</span> 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.
       </p><p>
        Presently, the commands emitted for <code class="option">--disable-triggers</code>
        must be done as superuser.  So, you should also specify
        a superuser name with <code class="option">-S</code>, or preferably be careful to
        start the resulting script as a superuser.
       </p><p>
        This option is ignored when emitting an archive (non-text) output
        file.  For the archive formats, you can specify the option when you
        call <code class="command">pg_restore</code>.
       </p></dd><dt><span class="term"><code class="option">--enable-row-security</code></span></dt><dd><p>
        This option is relevant only when dumping the contents of a table
        which has row security.  By default, <span class="application">pg_dump</span> will set
        <a class="xref" href="runtime-config-client.html#GUC-ROW-SECURITY">row_security</a> to off, to ensure
        that all data is dumped from the table.  If the user does not have
        sufficient privileges to bypass row security, then an error is thrown.
        This parameter instructs <span class="application">pg_dump</span> to set
        <a class="xref" href="runtime-config-client.html#GUC-ROW-SECURITY">row_security</a> to on instead, allowing the user
        to dump the parts of the contents of the table that they have access to.
       </p><p>
        Note that if you use this option currently, you probably also want
        the dump be in <code class="command">INSERT</code> format, as the
        <code class="command">COPY FROM</code> during restore does not support row security.
       </p></dd><dt><span class="term"><code class="option">--exclude-table-data=<em class="replaceable"><code>pattern</code></em></code></span></dt><dd><p>
        Do not dump data for any tables matching <em class="replaceable"><code>pattern</code></em>. The pattern is
        interpreted according to the same rules as for <code class="option">-t</code>.
        <code class="option">--exclude-table-data</code> can be given more than once to
        exclude tables matching any of several patterns. This option is
        useful when you need the definition of a particular table even
        though you do not need the data in it.
       </p><p>
        To exclude data for all tables in the database, see <code class="option">--schema-only</code>.
       </p></dd><dt><span class="term"><code class="option">--extra-float-digits=<em class="replaceable"><code>ndigits</code></em></code></span></dt><dd><p>
        Use the specified value of <code class="option">extra_float_digits</code> when dumping
        floating-point data, instead of the maximum available precision.
        Routine dumps made for backup purposes should not use this option.
       </p></dd><dt><span class="term"><code class="option">--if-exists</code></span></dt><dd><p>
        Use <code class="literal">DROP ... IF EXISTS</code> commands to drop objects
        in <code class="option">--clean</code> mode.  This suppresses <span class="quote"><span class="quote">does not
        exist</span></span> errors that might otherwise be reported.  This
        option is not valid unless <code class="option">--clean</code> is also
        specified.
       </p></dd><dt><span class="term"><code class="option">--include-foreign-data=<em class="replaceable"><code>foreignserver</code></em></code></span></dt><dd><p>
        Dump the data for any foreign table with a foreign server
        matching <em class="replaceable"><code>foreignserver</code></em>
        pattern. Multiple foreign servers can be selected by writing multiple
        <code class="option">--include-foreign-data</code> switches.
        Also, the <em class="replaceable"><code>foreignserver</code></em> parameter is
        interpreted as a pattern according to the same rules used by
        <span class="application">psql</span>'s <code class="literal">\d</code> commands
        (see <a class="xref" href="app-psql.html#APP-PSQL-PATTERNS" title="Patterns">Patterns</a> below),
        so multiple foreign servers can also be selected by writing wildcard characters
        in the pattern.  When using wildcards, be careful to quote the pattern
        if needed to prevent the shell from expanding the wildcards; see
        <a class="xref" href="app-pgdump.html#PG-DUMP-EXAMPLES" title="Examples">Examples</a> below.
        The only exception is that an empty pattern is disallowed.
       </p><div class="note"><h3 class="title">Note</h3><p>
         When <code class="option">--include-foreign-data</code> is specified,
         <span class="application">pg_dump</span> does not check that the foreign
         table is writable.  Therefore, there is no guarantee that the
         results of a foreign table dump can be successfully restored.
        </p></div></dd><dt><span class="term"><code class="option">--inserts</code></span></dt><dd><p>
        Dump data as <code class="command">INSERT</code> commands (rather
        than <code class="command">COPY</code>).  This will make restoration very slow;
        it is mainly useful for making dumps that can be loaded into
        non-<span class="productname">PostgreSQL</span> databases.
        Any error during restoring will cause only rows that are part of the
        problematic <code class="command">INSERT</code> to be lost, rather than the
        entire table contents.  Note that the restore might fail altogether if
        you have rearranged column order.  The
        <code class="option">--column-inserts</code> option is safe against column order
        changes, though even slower.
       </p></dd><dt><span class="term"><code class="option">--load-via-partition-root</code></span></dt><dd><p>
        When dumping data for a table partition, make
        the <code class="command">COPY</code> or <code class="command">INSERT</code> 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.
       </p></dd><dt><span class="term"><code class="option">--lock-wait-timeout=<em class="replaceable"><code>timeout</code></em></code></span></dt><dd><p>
        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
        <em class="replaceable"><code>timeout</code></em>. The timeout may be
        specified in any of the formats accepted by <code class="command">SET
        statement_timeout</code>.  (Allowed formats vary depending on the server
        version you are dumping from, but an integer number of milliseconds
        is accepted by all versions.)
       </p></dd><dt><span class="term"><code class="option">--no-comments</code></span></dt><dd><p>
        Do not dump comments.
       </p></dd><dt><span class="term"><code class="option">--no-publications</code></span></dt><dd><p>
        Do not dump publications.
       </p></dd><dt><span class="term"><code class="option">--no-security-labels</code></span></dt><dd><p>
        Do not dump security labels.
       </p></dd><dt><span class="term"><code class="option">--no-subscriptions</code></span></dt><dd><p>
        Do not dump subscriptions.
       </p></dd><dt><span class="term"><code class="option">--no-sync</code></span></dt><dd><p>
        By default, <code class="command">pg_dump</code> will wait for all files
        to be written safely to disk.  This option causes
        <code class="command">pg_dump</code> 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.
       </p></dd><dt><span class="term"><code class="option">--no-table-access-method</code></span></dt><dd><p>
        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.
       </p><p>
        This option is ignored when emitting an archive (non-text) output
        file.  For the archive formats, you can specify the option when you
        call <code class="command">pg_restore</code>.
       </p></dd><dt><span class="term"><code class="option">--no-tablespaces</code></span></dt><dd><p>
        Do not output commands to select tablespaces.
        With this option, all objects will be created in whichever
        tablespace is the default during restore.
       </p><p>
        This option is ignored when emitting an archive (non-text) output
        file.  For the archive formats, you can specify the option when you
        call <code class="command">pg_restore</code>.
       </p></dd><dt><span class="term"><code class="option">--no-toast-compression</code></span></dt><dd><p>
        Do not output commands to set <acronym class="acronym">TOAST</acronym> compression
        methods.
        With this option, all columns will be restored with the default
        compression setting.
       </p></dd><dt><span class="term"><code class="option">--no-unlogged-table-data</code></span></dt><dd><p>
        Do not dump the contents of unlogged tables and sequences.  This
        option has no effect on whether or not the table and sequence
        definitions (schema) are dumped; it only suppresses dumping the table
        and sequence data. Data in unlogged tables and sequences
        is always excluded when dumping from a standby server.
       </p></dd><dt><span class="term"><code class="option">--on-conflict-do-nothing</code></span></dt><dd><p>
        Add <code class="literal">ON CONFLICT DO NOTHING</code> to
        <code class="command">INSERT</code> commands.
        This option is not valid unless <code class="option">--inserts</code>,
        <code class="option">--column-inserts</code> or
        <code class="option">--rows-per-insert</code> is also specified.
       </p></dd><dt><span class="term"><code class="option">--quote-all-identifiers</code></span></dt><dd><p>
        Force quoting of all identifiers.  This option is recommended when
        dumping a database from a server whose <span class="productname">PostgreSQL</span>
        major version is different from <span class="application">pg_dump</span>'s, or when
        the output is intended to be loaded into a server of a different
        major version.  By default, <span class="application">pg_dump</span> 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 <code class="option">--quote-all-identifiers</code> prevents
        such issues, at the price of a harder-to-read dump script.
       </p></dd><dt><span class="term"><code class="option">--rows-per-insert=<em class="replaceable"><code>nrows</code></em></code></span></dt><dd><p>
        Dump data as <code class="command">INSERT</code> commands (rather than
        <code class="command">COPY</code>).  Controls the maximum number of rows per
        <code class="command">INSERT</code> 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 <code class="command">INSERT</code> to be
        lost, rather than the entire table contents.
       </p></dd><dt><span class="term"><code class="option">--section=<em class="replaceable"><code>sectionname</code></em></code></span></dt><dd><p>
          Only dump the named section. The section name can be
          <code class="option">pre-data</code>, <code class="option">data</code>, or <code class="option">post-data</code>.
          This option can be specified more than once to select multiple
          sections. The default is to dump all sections.
         </p><p>
          The data section contains actual table data, large-object
          contents, and sequence values.
          Post-data items include definitions of indexes, triggers, rules,
          and constraints other than validated check constraints.
          Pre-data items include all other data definition items.
         </p></dd><dt><span class="term"><code class="option">--serializable-deferrable</code></span></dt><dd><p>
        Use a <code class="literal">serializable</code> transaction for the dump, to
        ensure that the snapshot used is consistent with later database
        states; but do this by waiting for a point in the transaction stream
        at which no anomalies can be present, so that there isn't a risk of
        the dump failing or causing other transactions to roll back with a
        <code class="literal">serialization_failure</code>.  See <a class="xref" href="mvcc.html" title="Chapter 13. Concurrency Control">Chapter 13</a>
        for more information about transaction isolation and concurrency
        control.
       </p><p>
        This option is not beneficial for a dump which is intended only for
        disaster recovery.  It could be useful for a dump used to load a
        copy of the database for reporting or other read-only load sharing
        while the original database continues to be updated.  Without it the
        dump may reflect a state which is not consistent with any serial
        execution of the transactions eventually committed.  For example, if
        batch processing techniques are used, a batch may show as closed in
        the dump without all of the items which are in the batch appearing.
       </p><p>
        This option will make no difference if there are no read-write
        transactions active when pg_dump is started.  If read-write
        transactions are active, the start of the dump may be delayed for an
        indeterminate length of time.  Once running, performance with or
        without the switch is the same.
       </p></dd><dt><span class="term"><code class="option">--snapshot=<em class="replaceable"><code>snapshotname</code></em></code></span></dt><dd><p>
          Use the specified synchronized snapshot when making a dump of the
          database (see
          <a class="xref" href="functions-admin.html#FUNCTIONS-SNAPSHOT-SYNCHRONIZATION-TABLE" title="Table 9.92. Snapshot Synchronization Functions">Table 9.92</a> for more
          details).
         </p><p>
          This option is useful when needing to synchronize the dump with
          a logical replication slot (see <a class="xref" href="logicaldecoding.html" title="Chapter 49. Logical Decoding">Chapter 49</a>)
          or with a concurrent session.
         </p><p>
          In the case of a parallel dump, the snapshot name defined by this
          option is used rather than taking a new snapshot.
         </p></dd><dt><span class="term"><code class="option">--strict-names</code></span></dt><dd><p>
        Require that each
        extension (<code class="option">-e</code>/<code class="option">--extension</code>),
        schema (<code class="option">-n</code>/<code class="option">--schema</code>) and
        table (<code class="option">-t</code>/<code class="option">--table</code>) qualifier
        match at least one extension/schema/table in the database to be dumped.
        Note that if none of the extension/schema/table qualifiers find
        matches, <span class="application">pg_dump</span> will generate an error
        even without <code class="option">--strict-names</code>.
       </p><p>
        This option has no effect
        on <code class="option">-N</code>/<code class="option">--exclude-schema</code>,
        <code class="option">-T</code>/<code class="option">--exclude-table</code>,
        or <code class="option">--exclude-table-data</code>.  An exclude pattern failing
        to match any objects is not considered an error.
       </p></dd><dt><span class="term"><code class="option">--use-set-session-authorization</code></span></dt><dd><p>
        Output SQL-standard <code class="command">SET SESSION AUTHORIZATION</code> commands
        instead of <code class="command">ALTER OWNER</code> 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.  Also, a dump using <code class="command">SET SESSION AUTHORIZATION</code>
        will certainly require superuser privileges to restore correctly,
        whereas <code class="command">ALTER OWNER</code> requires lesser privileges.
       </p></dd><dt><span class="term"><code class="option">-?</code><br /></span><span class="term"><code class="option">--help</code></span></dt><dd><p>
       Show help about <span class="application">pg_dump</span> command line
       arguments, and exit.
       </p></dd></dl></div><p>
   </p><p>
    The following command-line options control the database connection parameters.

    </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="option">-d <em class="replaceable"><code>dbname</code></em></code><br /></span><span class="term"><code class="option">--dbname=<em class="replaceable"><code>dbname</code></em></code></span></dt><dd><p>
       Specifies the name of the database to connect to. This is
       equivalent to specifying <em class="replaceable"><code>dbname</code></em> as the first non-option
       argument on the command line.  The <em class="replaceable"><code>dbname</code></em>
       can be a <a class="link" href="libpq-connect.html#LIBPQ-CONNSTRING" title="34.1.1. Connection Strings">connection string</a>.
       If so, connection string parameters will override any conflicting
       command line options.
      </p></dd><dt><span class="term"><code class="option">-h <em class="replaceable"><code>host</code></em></code><br /></span><span class="term"><code class="option">--host=<em class="replaceable"><code>host</code></em></code></span></dt><dd><p>
        Specifies the host name of the machine on which the 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 <code class="envar">PGHOST</code> environment variable, if set,
        else a Unix domain socket connection is attempted.
       </p></dd><dt><span class="term"><code class="option">-p <em class="replaceable"><code>port</code></em></code><br /></span><span class="term"><code class="option">--port=<em class="replaceable"><code>port</code></em></code></span></dt><dd><p>
        Specifies the TCP port or local Unix domain socket file
        extension on which the server is listening for connections.
        Defaults to the <code class="envar">PGPORT</code> environment variable, if
        set, or a compiled-in default.
       </p></dd><dt><span class="term"><code class="option">-U <em class="replaceable"><code>username</code></em></code><br /></span><span class="term"><code class="option">--username=<em class="replaceable"><code>username</code></em></code></span></dt><dd><p>
        User name to connect as.
       </p></dd><dt><span class="term"><code class="option">-w</code><br /></span><span class="term"><code class="option">--no-password</code></span></dt><dd><p>
        Never issue a password prompt.  If the server requires
        password authentication and a password is not available by
        other means such as a <code class="filename">.pgpass</code> 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.
       </p></dd><dt><span class="term"><code class="option">-W</code><br /></span><span class="term"><code class="option">--password</code></span></dt><dd><p>
        Force <span class="application">pg_dump</span> to prompt for a
        password before connecting to a database.
       </p><p>
        This option is never essential, since
        <span class="application">pg_dump</span> will automatically prompt
        for a password if the server demands password authentication.
        However, <span class="application">pg_dump</span> will waste a
        connection attempt finding out that the server wants a password.
        In some cases it is worth typing <code class="option">-W</code> to avoid the extra
        connection attempt.
       </p></dd><dt><span class="term"><code class="option">--role=<em class="replaceable"><code>rolename</code></em></code></span></dt><dd><p>
        Specifies a role name to be used to create the dump.
        This option causes <span class="application">pg_dump</span> to issue a
        <code class="command">SET ROLE</code> <em class="replaceable"><code>rolename</code></em>
        command after connecting to the database. It is useful when the
        authenticated user (specified by <code class="option">-U</code>) lacks privileges
        needed by <span class="application">pg_dump</span>, 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.
       </p></dd></dl></div><p>
   </p></div><div class="refsect1" id="id-1.9.4.13.7"><h2>Environment</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="envar">PGDATABASE</code><br /></span><span class="term"><code class="envar">PGHOST</code><br /></span><span class="term"><code class="envar">PGOPTIONS</code><br /></span><span class="term"><code class="envar">PGPORT</code><br /></span><span class="term"><code class="envar">PGUSER</code></span></dt><dd><p>
      Default connection parameters.
     </p></dd><dt><span class="term"><code class="envar">PG_COLOR</code></span></dt><dd><p>
      Specifies whether to use color in diagnostic messages. Possible values
      are <code class="literal">always</code>, <code class="literal">auto</code> and
      <code class="literal">never</code>.
     </p></dd></dl></div><p>
   This utility, like most other <span class="productname">PostgreSQL</span> utilities,
   also uses the environment variables supported by <span class="application">libpq</span>
   (see <a class="xref" href="libpq-envars.html" title="34.15. Environment Variables">Section 34.15</a>).
  </p></div><div class="refsect1" id="APP-PGDUMP-DIAGNOSTICS"><h2>Diagnostics</h2><p>
   <span class="application">pg_dump</span> internally executes
   <code class="command">SELECT</code> statements. If you have problems running
   <span class="application">pg_dump</span>, make sure you are able to
   select information from the database using, for example, <a class="xref" href="app-psql.html" title="psql"><span class="refentrytitle"><span class="application">psql</span></span></a>.  Also, any default connection settings and environment
   variables used by the <span class="application">libpq</span> front-end
   library will apply.
  </p><p>
   The database activity of <span class="application">pg_dump</span> is
   normally collected by the cumulative statistics system.  If this is
   undesirable, you can set parameter <code class="varname">track_counts</code>
   to false via <code class="envar">PGOPTIONS</code> or the <code class="literal">ALTER
   USER</code> command.
  </p></div><div class="refsect1" id="PG-DUMP-NOTES"><h2>Notes</h2><p>
   If your database cluster has any local additions to the <code class="literal">template1</code> database,
   be careful to restore the output of <span class="application">pg_dump</span> into a
   truly empty database; otherwise you are likely to get errors due to
   duplicate definitions of the added objects.  To make an empty database
   without any local additions, copy from <code class="literal">template0</code> not <code class="literal">template1</code>,
   for example:
</p><pre class="programlisting">
CREATE DATABASE foo WITH TEMPLATE template0;
</pre><p>
  </p><p>
   When a data-only dump is chosen and the option <code class="option">--disable-triggers</code>
   is used, <span class="application">pg_dump</span> emits commands
   to disable triggers on user tables before inserting the data,
   and then commands to re-enable them after the data has been
   inserted.  If the restore is stopped in the middle, the system
   catalogs might be left in the wrong state.
  </p><p>
   The dump file produced by <span class="application">pg_dump</span>
   does not contain the statistics used by the optimizer to make
   query planning decisions.  Therefore, it is wise to run
   <code class="command">ANALYZE</code> after restoring from a dump file
   to ensure optimal performance; see <a class="xref" href="routine-vacuuming.html#VACUUM-FOR-STATISTICS" title="25.1.3. Updating Planner Statistics">Section 25.1.3</a>
   and <a class="xref" href="routine-vacuuming.html#AUTOVACUUM" title="25.1.6. The Autovacuum Daemon">Section 25.1.6</a> for more information.
  </p><p>
   Because <span class="application">pg_dump</span> is used to transfer data
   to newer versions of <span class="productname">PostgreSQL</span>, the output of
   <span class="application">pg_dump</span> can be expected to load into
   <span class="productname">PostgreSQL</span> server versions newer than
   <span class="application">pg_dump</span>'s version.  <span class="application">pg_dump</span> can also
   dump from <span class="productname">PostgreSQL</span> servers older than its own version.
   (Currently, servers back to version 9.2 are supported.)
   However, <span class="application">pg_dump</span> cannot dump from
   <span class="productname">PostgreSQL</span> servers newer than its own major version;
   it will refuse to even try, rather than risk making an invalid dump.
   Also, it is not guaranteed that <span class="application">pg_dump</span>'s output can
   be loaded into a server of an older major version — not even if the
   dump was taken from a server of that version.  Loading a dump file
   into an older server may require manual editing of the dump file
   to remove syntax not understood by the older server.
   Use of the <code class="option">--quote-all-identifiers</code> option is recommended
   in cross-version cases, as it can prevent problems arising from varying
   reserved-word lists in different <span class="productname">PostgreSQL</span> versions.
  </p><p>
   When dumping logical replication subscriptions,
   <span class="application">pg_dump</span> will generate <code class="command">CREATE
   SUBSCRIPTION</code> commands that use the <code class="literal">connect = false</code>
   option, so that restoring the subscription does not make remote connections
   for creating a replication slot or for initial table copy.  That way, the
   dump can be restored without requiring network access to the remote
   servers.  It is then up to the user to reactivate the subscriptions in a
   suitable way.  If the involved hosts have changed, the connection
   information might have to be changed.  It might also be appropriate to
   truncate the target tables before initiating a new full table copy.  If users
   intend to copy initial data during refresh they must create the slot with
   <code class="literal">two_phase = false</code>.  After the initial sync, the
   <code class="literal">two_phase</code> option will be automatically enabled by the
   subscriber if the subscription had been originally created with
   <code class="literal">two_phase = true</code> option.
  </p></div><div class="refsect1" id="PG-DUMP-EXAMPLES"><h2>Examples</h2><p>
   To dump a database called <code class="literal">mydb</code> into an SQL-script file:
</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump mydb &gt; db.sql</code></strong>
</pre><p>
  </p><p>
   To reload such a script into a (freshly created) database named
   <code class="literal">newdb</code>:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>psql -d newdb -f db.sql</code></strong>
</pre><p>
  </p><p>
   To dump a database into a custom-format archive file:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -Fc mydb &gt; db.dump</code></strong>
</pre><p>
  </p><p>
   To dump a database into a directory-format archive:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -Fd mydb -f dumpdir</code></strong>
</pre><p>
  </p><p>
   To dump a database into a directory-format archive in parallel with
   5 worker jobs:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -Fd mydb -j 5 -f dumpdir</code></strong>
</pre><p>
  </p><p>
   To reload an archive file into a (freshly created) database named
   <code class="literal">newdb</code>:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_restore -d newdb db.dump</code></strong>
</pre><p>
  </p><p>
   To reload an archive file into the same database it was dumped from,
   discarding the current contents of that database:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_restore -d postgres --clean --create db.dump</code></strong>
</pre><p>
  </p><p>
   To dump a single table named <code class="literal">mytab</code>:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -t mytab mydb &gt; db.sql</code></strong>
</pre><p>
  </p><p>
   To dump all tables whose names start with <code class="literal">emp</code> in the
   <code class="literal">detroit</code> schema, except for the table named
   <code class="literal">employee_log</code>:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -t 'detroit.emp*' -T detroit.employee_log mydb &gt; db.sql</code></strong>
</pre><p>
  </p><p>
   To dump all schemas whose names start with <code class="literal">east</code> or
   <code class="literal">west</code> and end in <code class="literal">gsm</code>, excluding any schemas whose
   names contain the word <code class="literal">test</code>:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -n 'east*gsm' -n 'west*gsm' -N '*test*' mydb &gt; db.sql</code></strong>
</pre><p>
  </p><p>
   The same, using regular expression notation to consolidate the switches:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -n '(east|west)*gsm' -N '*test*' mydb &gt; db.sql</code></strong>
</pre><p>
  </p><p>
   To dump all database objects except for tables whose names begin with
   <code class="literal">ts_</code>:

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -T 'ts_*' mydb &gt; db.sql</code></strong>
</pre><p>
  </p><p>
   To specify an upper-case or mixed-case name in <code class="option">-t</code> and related
   switches, you need to double-quote the name; else it will be folded to
   lower case (see <a class="xref" href="app-psql.html#APP-PSQL-PATTERNS" title="Patterns">Patterns</a> below).  But
   double quotes are special to the shell, so in turn they must be quoted.
   Thus, to dump a single table with a mixed-case name, you need something
   like

</p><pre class="screen">
<code class="prompt">$</code> <strong class="userinput"><code>pg_dump -t "\"MixedCaseName\"" mydb &gt; mytab.sql</code></strong>
</pre></div><div class="refsect1" id="id-1.9.4.13.11"><h2>See Also</h2><span class="simplelist"><a class="xref" href="app-pg-dumpall.html" title="pg_dumpall"><span class="refentrytitle"><span class="application">pg_dumpall</span></span></a>, <a class="xref" href="app-pgrestore.html" title="pg_restore"><span class="refentrytitle"><span class="application">pg_restore</span></span></a>, <a class="xref" href="app-psql.html" title="psql"><span class="refentrytitle"><span class="application">psql</span></span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="app-pgconfig.html" title="pg_config">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="reference-client.html" title="PostgreSQL Client Applications">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="app-pg-dumpall.html" title="pg_dumpall">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="application">pg_config</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> <span class="application">pg_dumpall</span></td></tr></table></div></body></html>