| <!-- |
| $PostgreSQL: pgsql/doc/src/sgml/ref/show.sgml,v 1.47 2008/11/14 10:22:47 petere Exp $ |
| PostgreSQL documentation |
| --> |
| |
| <refentry id="SQL-SHOW"> |
| <refmeta> |
| <refentrytitle id="SQL-SHOW-TITLE">SHOW</refentrytitle> |
| <manvolnum>7</manvolnum> |
| <refmiscinfo>SQL - Language Statements</refmiscinfo> |
| </refmeta> |
| |
| <refnamediv> |
| <refname>SHOW</refname> |
| <refpurpose>show the value of a run-time parameter</refpurpose> |
| </refnamediv> |
| |
| <indexterm zone="sql-show"> |
| <primary>SHOW</primary> |
| </indexterm> |
| |
| <refsynopsisdiv> |
| <synopsis> |
| SHOW <replaceable class="PARAMETER">name</replaceable> |
| SHOW ALL |
| </synopsis> |
| </refsynopsisdiv> |
| |
| <refsect1> |
| <title>Description</title> |
| |
| <para> |
| <command>SHOW</command> will display the current setting of |
| run-time parameters. These variables can be set using the |
| <command>SET</command> statement, by editing the |
| <filename>postgresql.conf</filename> configuration file, through |
| the <envar>PGOPTIONS</envar> environmental variable (when using |
| <application>libpq</> or a <application>libpq</>-based |
| application), or through command-line flags when starting the |
| <command>postgres</command> server. See <xref |
| linkend="runtime-config"> for details. |
| </para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Parameters</title> |
| |
| <variablelist> |
| <varlistentry> |
| <term><replaceable class="PARAMETER">name</replaceable></term> |
| <listitem> |
| <para> |
| The name of a run-time parameter. Available parameters are |
| documented in <xref linkend="runtime-config"> and on the <xref |
| linkend="SQL-SET" endterm="SQL-SET-title"> reference page. In |
| addition, there are a few parameters that can be shown but not |
| set: |
| |
| <variablelist> |
| <varlistentry> |
| <term><literal>SERVER_VERSION</literal></term> |
| <listitem> |
| <para> |
| Shows the server's version number. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><literal>SERVER_ENCODING</literal></term> |
| <listitem> |
| <para> |
| Shows the server-side character set encoding. At present, |
| this parameter can be shown but not set, because the |
| encoding is determined at database creation time. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><literal>LC_COLLATE</literal></term> |
| <listitem> |
| <para> |
| Shows the database's locale setting for collation (text |
| ordering). At present, this parameter can be shown but not |
| set, because the setting is determined at database creation |
| time. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><literal>LC_CTYPE</literal></term> |
| <listitem> |
| <para> |
| Shows the database's locale setting for character |
| classification. At present, this parameter can be shown but |
| not set, because the setting is determined at database creation |
| time. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><literal>IS_SUPERUSER</literal></term> |
| <listitem> |
| <para> |
| True if the current role has superuser privileges. |
| </para> |
| </listitem> |
| </varlistentry> |
| </variablelist> |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><literal>ALL</literal></term> |
| <listitem> |
| <para> |
| Show the values of all configuration parameters, with descriptions. |
| </para> |
| </listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>Notes</title> |
| |
| <para> |
| The function <function>current_setting</function> produces |
| equivalent output; see <xref linkend="functions-admin">. |
| Also, the |
| <link linkend="view-pg-settings"><structname>pg_settings</structname></link> |
| system view produces the same information. |
| |
| </para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Examples</title> |
| |
| <para> |
| Show the current setting of the parameter <varname>DateStyle</varname>: |
| |
| <programlisting> |
| SHOW DateStyle; |
| DateStyle |
| ----------- |
| ISO, MDY |
| (1 row) |
| </programlisting> |
| </para> |
| |
| <para> |
| Show the current setting of the parameter <varname>geqo</varname>: |
| <programlisting> |
| SHOW geqo; |
| geqo |
| ------ |
| on |
| (1 row) |
| </programlisting> |
| </para> |
| |
| <para> |
| Show all settings: |
| <programlisting> |
| SHOW ALL; |
| name | setting | description |
| --------------------------------+--------------------------------+---------------------------------------------------------------------------------------------- |
| add_missing_from | off | Automatically adds missing table references to FROM clauses. |
| allow_system_table_mods | off | Allows modifications of the structure of system tables. |
| . |
| . |
| . |
| work_mem | 1024 | Sets the maximum memory to be used for query workspaces. |
| zero_damaged_pages | off | Continues processing past damaged page headers. |
| (146 rows) |
| </programlisting> |
| </para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Compatibility</title> |
| |
| <para> |
| The <command>SHOW</command> command is a |
| <productname>PostgreSQL</productname> extension. |
| </para> |
| </refsect1> |
| |
| <refsect1> |
| <title>See Also</title> |
| |
| <simplelist type="inline"> |
| <member><xref linkend="SQL-SET" endterm="SQL-SET-title"></member> |
| <member><xref linkend="SQL-RESET" endterm="SQL-RESET-title"></member> |
| </simplelist> |
| </refsect1> |
| |
| </refentry> |