<!-- doc/src/sgml/vacuumlo.sgml -->

<refentry id="vacuumlo">
 <indexterm zone="vacuumlo">
  <primary>vacuumlo</primary>
 </indexterm>

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

 <refnamediv>
  <refname>vacuumlo</refname>
  <refpurpose>remove orphaned large objects from a <productname>PostgreSQL</productname> database</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
  <cmdsynopsis>
   <command>vacuumlo</command>
   <arg choice="opt" rep="repeat"><replaceable>option</replaceable></arg>
   <arg choice="plain" rep="repeat"><replaceable>dbname</replaceable></arg>
  </cmdsynopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

 <para>
  <application>vacuumlo</application> is a simple utility program that will remove any
  <quote>orphaned</quote> large objects from a
  <productname>PostgreSQL</productname> database.  An orphaned large object (LO) is
  considered to be any LO whose OID does not appear in any <type>oid</type> or
  <type>lo</type> data column of the database.
 </para>

 <para>
  If you use this, you may also be interested in the <function>lo_manage</function>
  trigger in the <xref linkend="lo"/> module.
  <function>lo_manage</function> is useful to try
  to avoid creating orphaned LOs in the first place.
 </para>

  <para>
   All databases named on the command line are processed.
  </para>
 </refsect1>

 <refsect1>
  <title>Options</title>

  <para>
   <application>vacuumlo</application> accepts the following command-line arguments:

  <variablelist>
   <varlistentry>
    <term><option>-l <replaceable class="parameter">limit</replaceable></option></term>
    <term><option>--limit=<replaceable class="parameter">limit</replaceable></option></term>
    <listitem>
     <para>
      Remove no more than <replaceable>limit</replaceable> large objects per
      transaction (default 1000).  Since the server acquires a lock per LO
      removed, removing too many LOs in one transaction risks exceeding
      <xref linkend="guc-max-locks-per-transaction"/>.  Set the limit to
      zero if you want all removals done in a single transaction.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><option>-n</option></term>
    <term><option>--dry-run</option></term>
    <listitem>
     <para>Don't remove anything, just show what would be done.</para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><option>-v</option></term>
    <term><option>--verbose</option></term>
    <listitem>
     <para>Write a lot of progress messages.</para>
    </listitem>
   </varlistentry>

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

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

  <para>
   <application>vacuumlo</application> also accepts the following command-line
   arguments for connection parameters:

  <variablelist>
   <varlistentry>
    <term><option>-h <replaceable class="parameter">host</replaceable></option></term>
    <term><option>--host=<replaceable class="parameter">host</replaceable></option></term>