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diff --git a/doc/src/sgml/vacuumlo.sgml b/doc/src/sgml/vacuumlo.sgml new file mode 100644 index 0000000..26b764d --- /dev/null +++ b/doc/src/sgml/vacuumlo.sgml @@ -0,0 +1,231 @@ +<!-- 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> + <listitem> + <para>Database server's host.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-p <replaceable>port</replaceable></option></term> + <term><option>--port=<replaceable class="parameter">port</replaceable></option></term> + <listitem> + <para>Database server's port.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-U <replaceable>username</replaceable></option></term> + <term><option>--username=<replaceable class="parameter">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>vacuumlo</application> to prompt for a + password before connecting to a database. + </para> + + <para> + This option is never essential, since + <application>vacuumlo</application> will automatically prompt + for a password if the server demands password authentication. + However, <application>vacuumlo</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> + </listitem> + </varlistentry> + </variablelist> + </para> + </refsect1> + + <refsect1> + <title>Environment</title> + + <variablelist> + <varlistentry> + <term><envar>PGHOST</envar></term> + <term><envar>PGPORT</envar></term> + <term><envar>PGUSER</envar></term> + + <listitem> + <para> + Default connection parameters. + </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> + + <para> + The environment variable <envar>PG_COLOR</envar> specifies whether to use + color in diagnostic messages. Possible values are + <literal>always</literal>, <literal>auto</literal> and + <literal>never</literal>. + </para> + </refsect1> + + <refsect1> + <title>Notes</title> + + <para> + <application>vacuumlo</application> works by the following method: + First, <application>vacuumlo</application> builds a temporary table which contains all + of the OIDs of the large objects in the selected database. It then scans + through all columns in the database that are of type + <type>oid</type> or <type>lo</type>, and removes matching entries from the temporary + table. (Note: Only types with these names are considered; in particular, + domains over them are not considered.) The remaining entries in the + temporary table identify orphaned LOs. These are removed. + </para> + </refsect1> + + <refsect1> + <title>Author</title> + + <para> + Peter Mount <email>peter@retep.org.uk</email> + </para> + </refsect1> + +</refentry> |