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   2 <!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>23.3. Character Set Support</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="collation.html" title="23.2. Collation Support" /><link rel="next" href="maintenance.html" title="Chapter 24. Routine Database Maintenance Tasks" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">23.3. Character Set Support</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="collation.html" title="23.2. Collation Support">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="charset.html" title="Chapter 23. Localization">Up</a></td><th width="60%" align="center">Chapter 23. Localization</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="maintenance.html" title="Chapter 24. Routine Database Maintenance Tasks">Next</a></td></tr></table><hr /></div><div class="sect1" id="MULTIBYTE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">23.3. Character Set Support <a href="#MULTIBYTE" class="id_link">#</a></h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="multibyte.html#MULTIBYTE-CHARSET-SUPPORTED">23.3.1. Supported Character Sets</a></span></dt><dt><span class="sect2"><a href="multibyte.html#MULTIBYTE-SETTING">23.3.2. Setting the Character Set</a></span></dt><dt><span class="sect2"><a href="multibyte.html#MULTIBYTE-AUTOMATIC-CONVERSION">23.3.3. Automatic Character Set Conversion Between Server and Client</a></span></dt><dt><span class="sect2"><a href="multibyte.html#MULTIBYTE-CONVERSIONS-SUPPORTED">23.3.4. Available Character Set Conversions</a></span></dt><dt><span class="sect2"><a href="multibyte.html#MULTIBYTE-FURTHER-READING">23.3.5. Further Reading</a></span></dt></dl></div><a id="id-1.6.10.5.2" class="indexterm"></a><p>
   3    The character set support in <span class="productname">PostgreSQL</span>
   4    allows you to store text in a variety of character sets (also called
   5    encodings), including
   6    single-byte character sets such as the ISO 8859 series and
   7    multiple-byte character sets such as <acronym class="acronym">EUC</acronym> (Extended Unix
   8    Code), UTF-8, and Mule internal code.  All supported character sets
   9    can be used transparently by clients, but a few are not supported
  10    for use within the server (that is, as a server-side encoding).
  11    The default character set is selected while
  12    initializing your <span class="productname">PostgreSQL</span> database
  13    cluster using <code class="command">initdb</code>.  It can be overridden when you
  14    create a database, so you can have multiple
  15    databases each with a different character set.
  16   </p><p>
  17    An important restriction, however, is that each database's character set
  18    must be compatible with the database's <code class="envar">LC_CTYPE</code> (character
  19    classification) and <code class="envar">LC_COLLATE</code> (string sort order) locale
  20    settings. For <code class="literal">C</code> or
  21    <code class="literal">POSIX</code> locale, any character set is allowed, but for other
  22    libc-provided locales there is only one character set that will work
  23    correctly.
  24    (On Windows, however, UTF-8 encoding can be used with any locale.)
  25    If you have ICU support configured, ICU-provided locales can be used
  26    with most but not all server-side encodings.
  27   </p><div class="sect2" id="MULTIBYTE-CHARSET-SUPPORTED"><div class="titlepage"><div><div><h3 class="title">23.3.1. Supported Character Sets <a href="#MULTIBYTE-CHARSET-SUPPORTED" class="id_link">#</a></h3></div></div></div><p>
  28      <a class="xref" href="multibyte.html#CHARSET-TABLE" title="Table 23.3. PostgreSQL Character Sets">Table 23.3</a> shows the character sets available
  29      for use in <span class="productname">PostgreSQL</span>.
  30     </p><div class="table" id="CHARSET-TABLE"><p class="title"><strong>Table 23.3. <span class="productname">PostgreSQL</span> Character Sets</strong></p><div class="table-contents"><table class="table" summary="PostgreSQL Character Sets" border="1"><colgroup><col class="col1" /><col class="col2" /><col class="col3" /><col class="col4" /><col class="col5" /><col class="col6" /><col class="col7" /></colgroup><thead><tr><th>Name</th><th>Description</th><th>Language</th><th>Server?</th><th>ICU?</th><th>Bytes/Char</th><th>Aliases</th></tr></thead><tbody><tr><td><code class="literal">BIG5</code></td><td>Big Five</td><td>Traditional Chinese</td><td>No</td><td>No</td><td>1–2</td><td><code class="literal">WIN950</code>, <code class="literal">Windows950</code></td></tr><tr><td><code class="literal">EUC_CN</code></td><td>Extended UNIX Code-CN</td><td>Simplified Chinese</td><td>Yes</td><td>Yes</td><td>1–3</td><td> </td></tr><tr><td><code class="literal">EUC_JP</code></td><td>Extended UNIX Code-JP</td><td>Japanese</td><td>Yes</td><td>Yes</td><td>1–3</td><td> </td></tr><tr><td><code class="literal">EUC_JIS_2004</code></td><td>Extended UNIX Code-JP, JIS X 0213</td><td>Japanese</td><td>Yes</td><td>No</td><td>1–3</td><td> </td></tr><tr><td><code class="literal">EUC_KR</code></td><td>Extended UNIX Code-KR</td><td>Korean</td><td>Yes</td><td>Yes</td><td>1–3</td><td> </td></tr><tr><td><code class="literal">EUC_TW</code></td><td>Extended UNIX Code-TW</td><td>Traditional Chinese, Taiwanese</td><td>Yes</td><td>Yes</td><td>1–4</td><td> </td></tr><tr><td><code class="literal">GB18030</code></td><td>National Standard</td><td>Chinese</td><td>No</td><td>No</td><td>1–4</td><td> </td></tr><tr><td><code class="literal">GBK</code></td><td>Extended National Standard</td><td>Simplified Chinese</td><td>No</td><td>No</td><td>1–2</td><td><code class="literal">WIN936</code>, <code class="literal">Windows936</code></td></tr><tr><td><code class="literal">ISO_8859_5</code></td><td>ISO 8859-5, <acronym class="acronym">ECMA</acronym> 113</td><td>Latin/Cyrillic</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">ISO_8859_6</code></td><td>ISO 8859-6, <acronym class="acronym">ECMA</acronym> 114</td><td>Latin/Arabic</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">ISO_8859_7</code></td><td>ISO 8859-7, <acronym class="acronym">ECMA</acronym> 118</td><td>Latin/Greek</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">ISO_8859_8</code></td><td>ISO 8859-8, <acronym class="acronym">ECMA</acronym> 121</td><td>Latin/Hebrew</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">JOHAB</code></td><td><acronym class="acronym">JOHAB</acronym></td><td>Korean (Hangul)</td><td>No</td><td>No</td><td>1–3</td><td> </td></tr><tr><td><code class="literal">KOI8R</code></td><td><acronym class="acronym">KOI</acronym>8-R</td><td>Cyrillic (Russian)</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">KOI8</code></td></tr><tr><td><code class="literal">KOI8U</code></td><td><acronym class="acronym">KOI</acronym>8-U</td><td>Cyrillic (Ukrainian)</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">LATIN1</code></td><td>ISO 8859-1, <acronym class="acronym">ECMA</acronym> 94</td><td>Western European</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO88591</code></td></tr><tr><td><code class="literal">LATIN2</code></td><td>ISO 8859-2, <acronym class="acronym">ECMA</acronym> 94</td><td>Central European</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO88592</code></td></tr><tr><td><code class="literal">LATIN3</code></td><td>ISO 8859-3, <acronym class="acronym">ECMA</acronym> 94</td><td>South European</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO88593</code></td></tr><tr><td><code class="literal">LATIN4</code></td><td>ISO 8859-4, <acronym class="acronym">ECMA</acronym> 94</td><td>North European</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO88594</code></td></tr><tr><td><code class="literal">LATIN5</code></td><td>ISO 8859-9, <acronym class="acronym">ECMA</acronym> 128</td><td>Turkish</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO88599</code></td></tr><tr><td><code class="literal">LATIN6</code></td><td>ISO 8859-10, <acronym class="acronym">ECMA</acronym> 144</td><td>Nordic</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO885910</code></td></tr><tr><td><code class="literal">LATIN7</code></td><td>ISO 8859-13</td><td>Baltic</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO885913</code></td></tr><tr><td><code class="literal">LATIN8</code></td><td>ISO 8859-14</td><td>Celtic</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO885914</code></td></tr><tr><td><code class="literal">LATIN9</code></td><td>ISO 8859-15</td><td>LATIN1 with Euro and accents</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ISO885915</code></td></tr><tr><td><code class="literal">LATIN10</code></td><td>ISO 8859-16, <acronym class="acronym">ASRO</acronym> SR 14111</td><td>Romanian</td><td>Yes</td><td>No</td><td>1</td><td><code class="literal">ISO885916</code></td></tr><tr><td><code class="literal">MULE_INTERNAL</code></td><td>Mule internal code</td><td>Multilingual Emacs</td><td>Yes</td><td>No</td><td>1–4</td><td> </td></tr><tr><td><code class="literal">SJIS</code></td><td>Shift JIS</td><td>Japanese</td><td>No</td><td>No</td><td>1–2</td><td><code class="literal">Mskanji</code>, <code class="literal">ShiftJIS</code>, <code class="literal">WIN932</code>, <code class="literal">Windows932</code></td></tr><tr><td><code class="literal">SHIFT_JIS_2004</code></td><td>Shift JIS, JIS X 0213</td><td>Japanese</td><td>No</td><td>No</td><td>1–2</td><td> </td></tr><tr><td><code class="literal">SQL_ASCII</code></td><td>unspecified (see text)</td><td><span class="emphasis"><em>any</em></span></td><td>Yes</td><td>No</td><td>1</td><td> </td></tr><tr><td><code class="literal">UHC</code></td><td>Unified Hangul Code</td><td>Korean</td><td>No</td><td>No</td><td>1–2</td><td><code class="literal">WIN949</code>, <code class="literal">Windows949</code></td></tr><tr><td><code class="literal">UTF8</code></td><td>Unicode, 8-bit</td><td><span class="emphasis"><em>all</em></span></td><td>Yes</td><td>Yes</td><td>1–4</td><td><code class="literal">Unicode</code></td></tr><tr><td><code class="literal">WIN866</code></td><td>Windows CP866</td><td>Cyrillic</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ALT</code></td></tr><tr><td><code class="literal">WIN874</code></td><td>Windows CP874</td><td>Thai</td><td>Yes</td><td>No</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1250</code></td><td>Windows CP1250</td><td>Central European</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1251</code></td><td>Windows CP1251</td><td>Cyrillic</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">WIN</code></td></tr><tr><td><code class="literal">WIN1252</code></td><td>Windows CP1252</td><td>Western European</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1253</code></td><td>Windows CP1253</td><td>Greek</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1254</code></td><td>Windows CP1254</td><td>Turkish</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1255</code></td><td>Windows CP1255</td><td>Hebrew</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1256</code></td><td>Windows CP1256</td><td>Arabic</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1257</code></td><td>Windows CP1257</td><td>Baltic</td><td>Yes</td><td>Yes</td><td>1</td><td> </td></tr><tr><td><code class="literal">WIN1258</code></td><td>Windows CP1258</td><td>Vietnamese</td><td>Yes</td><td>Yes</td><td>1</td><td><code class="literal">ABC</code>, <code class="literal">TCVN</code>, <code class="literal">TCVN5712</code>, <code class="literal">VSCII</code></td></tr></tbody></table></div></div><br class="table-break" /><p>
  31       Not all client <acronym class="acronym">API</acronym>s support all the listed character sets. For example, the
  32       <span class="productname">PostgreSQL</span>
  33       JDBC driver does not support <code class="literal">MULE_INTERNAL</code>, <code class="literal">LATIN6</code>,
  34       <code class="literal">LATIN8</code>, and <code class="literal">LATIN10</code>.
  35      </p><p>
  36       The <code class="literal">SQL_ASCII</code> setting behaves considerably differently
  37       from the other settings.  When the server character set is
  38       <code class="literal">SQL_ASCII</code>, the server interprets byte values 0–127
  39       according to the ASCII standard, while byte values 128–255 are taken
  40       as uninterpreted characters.  No encoding conversion will be done when
  41       the setting is <code class="literal">SQL_ASCII</code>.  Thus, this setting is not so
  42       much a declaration that a specific encoding is in use, as a declaration
  43       of ignorance about the encoding.  In most cases, if you are
  44       working with any non-ASCII data, it is unwise to use the
  45       <code class="literal">SQL_ASCII</code> setting because
  46       <span class="productname">PostgreSQL</span> will be unable to help you by
  47       converting or validating non-ASCII characters.
  48      </p></div><div class="sect2" id="MULTIBYTE-SETTING"><div class="titlepage"><div><div><h3 class="title">23.3.2. Setting the Character Set <a href="#MULTIBYTE-SETTING" class="id_link">#</a></h3></div></div></div><p>
  49      <code class="command">initdb</code> defines the default character set (encoding)
  50      for a <span class="productname">PostgreSQL</span> cluster. For example,
  51
  52 </p><pre class="screen">
  53 initdb -E EUC_JP
  54 </pre><p>
  55
  56      sets the default character set to
  57      <code class="literal">EUC_JP</code> (Extended Unix Code for Japanese).  You
  58      can use <code class="option">--encoding</code> instead of
  59      <code class="option">-E</code> if you prefer longer option strings.
  60      If no <code class="option">-E</code> or <code class="option">--encoding</code> option is
  61      given, <code class="command">initdb</code> attempts to determine the appropriate
  62      encoding to use based on the specified or default locale.
  63     </p><p>
  64      You can specify a non-default encoding at database creation time,
  65      provided that the encoding is compatible with the selected locale:
  66
  67 </p><pre class="screen">
  68 createdb -E EUC_KR -T template0 --lc-collate=ko_KR.euckr --lc-ctype=ko_KR.euckr korean
  69 </pre><p>
  70
  71      This will create a database named <code class="literal">korean</code> that
  72      uses the character set <code class="literal">EUC_KR</code>, and locale <code class="literal">ko_KR</code>.
  73      Another way to accomplish this is to use this SQL command:
  74
  75 </p><pre class="programlisting">
  76 CREATE DATABASE korean WITH ENCODING 'EUC_KR' LC_COLLATE='ko_KR.euckr' LC_CTYPE='ko_KR.euckr' TEMPLATE=template0;
  77 </pre><p>
  78
  79      Notice that the above commands specify copying the <code class="literal">template0</code>
  80      database.  When copying any other database, the encoding and locale
  81      settings cannot be changed from those of the source database, because
  82      that might result in corrupt data.  For more information see
  83      <a class="xref" href="manage-ag-templatedbs.html" title="22.3. Template Databases">Section 22.3</a>.
  84     </p><p>
  85      The encoding for a database is stored in the system catalog
  86      <code class="literal">pg_database</code>.  You can see it by using the
  87      <code class="command">psql</code> <code class="option">-l</code> option or the
  88      <code class="command">\l</code> command.
  89
  90 </p><pre class="screen">
  91 $ <strong class="userinput"><code>psql -l</code></strong>
  92                                          List of databases
  93    Name    |  Owner   | Encoding  |  Collation  |    Ctype    |          Access Privileges
  94 -----------+----------+-----------+-------------+-------------+-------------------------------------
  95  clocaledb | hlinnaka | SQL_ASCII | C           | C           |
  96  englishdb | hlinnaka | UTF8      | en_GB.UTF8  | en_GB.UTF8  |
  97  japanese  | hlinnaka | UTF8      | ja_JP.UTF8  | ja_JP.UTF8  |
  98  korean    | hlinnaka | EUC_KR    | ko_KR.euckr | ko_KR.euckr |
  99  postgres  | hlinnaka | UTF8      | fi_FI.UTF8  | fi_FI.UTF8  |
 100  template0 | hlinnaka | UTF8      | fi_FI.UTF8  | fi_FI.UTF8  | {=c/hlinnaka,hlinnaka=CTc/hlinnaka}
 101  template1 | hlinnaka | UTF8      | fi_FI.UTF8  | fi_FI.UTF8  | {=c/hlinnaka,hlinnaka=CTc/hlinnaka}
 102 (7 rows)
 103 </pre><p>
 104     </p><div class="important"><h3 class="title">Important</h3><p>
 105       On most modern operating systems, <span class="productname">PostgreSQL</span>
 106       can determine which character set is implied by the <code class="envar">LC_CTYPE</code>
 107       setting, and it will enforce that only the matching database encoding is
 108       used.  On older systems it is your responsibility to ensure that you use
 109       the encoding expected by the locale you have selected.  A mistake in
 110       this area is likely to lead to strange behavior of locale-dependent
 111       operations such as sorting.
 112      </p><p>
 113       <span class="productname">PostgreSQL</span> will allow superusers to create
 114       databases with <code class="literal">SQL_ASCII</code> encoding even when
 115       <code class="envar">LC_CTYPE</code> is not <code class="literal">C</code> or <code class="literal">POSIX</code>.  As noted
 116       above, <code class="literal">SQL_ASCII</code> does not enforce that the data stored in
 117       the database has any particular encoding, and so this choice poses risks
 118       of locale-dependent misbehavior.  Using this combination of settings is
 119       deprecated and may someday be forbidden altogether.
 120      </p></div></div><div class="sect2" id="MULTIBYTE-AUTOMATIC-CONVERSION"><div class="titlepage"><div><div><h3 class="title">23.3.3. Automatic Character Set Conversion Between Server and Client <a href="#MULTIBYTE-AUTOMATIC-CONVERSION" class="id_link">#</a></h3></div></div></div><p>
 121      <span class="productname">PostgreSQL</span> supports automatic character
 122      set conversion between server and client for many combinations of
 123      character sets (<a class="xref" href="multibyte.html#MULTIBYTE-CONVERSIONS-SUPPORTED" title="23.3.4. Available Character Set Conversions">Section 23.3.4</a>
 124      shows which ones).
 125     </p><p>
 126      To enable automatic character set conversion, you have to
 127      tell <span class="productname">PostgreSQL</span> the character set
 128      (encoding) you would like to use in the client. There are several
 129      ways to accomplish this:
 130
 131      </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
 132         Using the <code class="command">\encoding</code> command in
 133         <span class="application">psql</span>.
 134         <code class="command">\encoding</code> allows you to change client
 135         encoding on the fly. For
 136         example, to change the encoding to <code class="literal">SJIS</code>, type:
 137
 138 </p><pre class="programlisting">
 139 \encoding SJIS
 140 </pre><p>
 141        </p></li><li class="listitem"><p>
 142         <span class="application">libpq</span> (<a class="xref" href="libpq-control.html" title="32.11. Control Functions">Section 32.11</a>) has functions to control the client encoding.
 143        </p></li><li class="listitem"><p>
 144         Using <code class="command">SET client_encoding TO</code>.
 145
 146         Setting the client encoding can be done with this SQL command:
 147
 148 </p><pre class="programlisting">
 149 SET CLIENT_ENCODING TO '<em class="replaceable"><code>value</code></em>';
 150 </pre><p>
 151
 152         Also you can use the standard SQL syntax <code class="literal">SET NAMES</code>
 153         for this purpose:
 154
 155 </p><pre class="programlisting">
 156 SET NAMES '<em class="replaceable"><code>value</code></em>';
 157 </pre><p>
 158
 159         To query the current client encoding:
 160
 161 </p><pre class="programlisting">
 162 SHOW client_encoding;
 163 </pre><p>
 164
 165         To return to the default encoding:
 166
 167 </p><pre class="programlisting">
 168 RESET client_encoding;
 169 </pre><p>
 170        </p></li><li class="listitem"><p>
 171         Using <code class="envar">PGCLIENTENCODING</code>. If the environment variable
 172         <code class="envar">PGCLIENTENCODING</code> is defined in the client's
 173         environment, that client encoding is automatically selected
 174         when a connection to the server is made.  (This can
 175         subsequently be overridden using any of the other methods
 176         mentioned above.)
 177        </p></li><li class="listitem"><p>
 178        Using the configuration variable <a class="xref" href="runtime-config-client.html#GUC-CLIENT-ENCODING">client_encoding</a>. If the
 179        <code class="varname">client_encoding</code> variable is set, that client
 180        encoding is automatically selected when a connection to the
 181        server is made.  (This can subsequently be overridden using any
 182        of the other methods mentioned above.)
 183        </p></li></ul></div><p>
 184     </p><p>
 185      If the conversion of a particular character is not possible
 186      — suppose you chose <code class="literal">EUC_JP</code> for the
 187      server and <code class="literal">LATIN1</code> for the client, and some
 188      Japanese characters are returned that do not have a representation in
 189      <code class="literal">LATIN1</code> — an error is reported.
 190     </p><p>
 191      If the client character set is defined as <code class="literal">SQL_ASCII</code>,
 192      encoding conversion is disabled, regardless of the server's character
 193      set.  (However, if the server's character set is
 194      not <code class="literal">SQL_ASCII</code>, the server will still check that
 195      incoming data is valid for that encoding; so the net effect is as
 196      though the client character set were the same as the server's.)
 197      Just as for the server, use of <code class="literal">SQL_ASCII</code> is unwise
 198      unless you are working with all-ASCII data.
 199     </p></div><div class="sect2" id="MULTIBYTE-CONVERSIONS-SUPPORTED"><div class="titlepage"><div><div><h3 class="title">23.3.4. Available Character Set Conversions <a href="#MULTIBYTE-CONVERSIONS-SUPPORTED" class="id_link">#</a></h3></div></div></div><p>
 200      <span class="productname">PostgreSQL</span> allows conversion between any
 201      two character sets for which a conversion function is listed in the
 202      <a class="link" href="catalog-pg-conversion.html" title="52.14. pg_conversion"><code class="structname">pg_conversion</code></a>
 203      system catalog.  <span class="productname">PostgreSQL</span> comes with
 204      some predefined conversions, as summarized in
 205      <a class="xref" href="multibyte.html#MULTIBYTE-TRANSLATION-TABLE" title="Table 23.4. Built-in Client/Server Character Set Conversions">Table 23.4</a> and shown in more
 206      detail in <a class="xref" href="multibyte.html#BUILTIN-CONVERSIONS-TABLE" title="Table 23.5. All Built-in Character Set Conversions">Table 23.5</a>.  You can
 207      create a new conversion using the SQL command
 208      <a class="xref" href="sql-createconversion.html" title="CREATE CONVERSION"><span class="refentrytitle">CREATE CONVERSION</span></a>.  (To be used for automatic
 209      client/server conversions, a conversion must be marked
 210      as <span class="quote">“<span class="quote">default</span>”</span> for its character set pair.)
 211     </p><div class="table" id="MULTIBYTE-TRANSLATION-TABLE"><p class="title"><strong>Table 23.4. Built-in Client/Server Character Set Conversions</strong></p><div class="table-contents"><table class="table" summary="Built-in Client/Server Character Set Conversions" border="1"><colgroup><col class="col1" /><col class="col2" /></colgroup><thead><tr><th>Server Character Set</th><th>Available Client Character Sets</th></tr></thead><tbody><tr><td><code class="literal">BIG5</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 212         </td></tr><tr><td><code class="literal">EUC_CN</code></td><td><span class="emphasis"><em>EUC_CN</em></span>,
 213         <code class="literal">MULE_INTERNAL</code>,
 214         <code class="literal">UTF8</code>
 215         </td></tr><tr><td><code class="literal">EUC_JP</code></td><td><span class="emphasis"><em>EUC_JP</em></span>,
 216         <code class="literal">MULE_INTERNAL</code>,
 217         <code class="literal">SJIS</code>,
 218         <code class="literal">UTF8</code>
 219         </td></tr><tr><td><code class="literal">EUC_JIS_2004</code></td><td><span class="emphasis"><em>EUC_JIS_2004</em></span>,
 220         <code class="literal">SHIFT_JIS_2004</code>,
 221         <code class="literal">UTF8</code>
 222         </td></tr><tr><td><code class="literal">EUC_KR</code></td><td><span class="emphasis"><em>EUC_KR</em></span>,
 223         <code class="literal">MULE_INTERNAL</code>,
 224         <code class="literal">UTF8</code>
 225         </td></tr><tr><td><code class="literal">EUC_TW</code></td><td><span class="emphasis"><em>EUC_TW</em></span>,
 226         <code class="literal">BIG5</code>,
 227         <code class="literal">MULE_INTERNAL</code>,
 228         <code class="literal">UTF8</code>
 229         </td></tr><tr><td><code class="literal">GB18030</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 230         </td></tr><tr><td><code class="literal">GBK</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 231         </td></tr><tr><td><code class="literal">ISO_8859_5</code></td><td><span class="emphasis"><em>ISO_8859_5</em></span>,
 232         <code class="literal">KOI8R</code>,
 233         <code class="literal">MULE_INTERNAL</code>,
 234         <code class="literal">UTF8</code>,
 235         <code class="literal">WIN866</code>,
 236         <code class="literal">WIN1251</code>
 237         </td></tr><tr><td><code class="literal">ISO_8859_6</code></td><td><span class="emphasis"><em>ISO_8859_6</em></span>,
 238         <code class="literal">UTF8</code>
 239         </td></tr><tr><td><code class="literal">ISO_8859_7</code></td><td><span class="emphasis"><em>ISO_8859_7</em></span>,
 240         <code class="literal">UTF8</code>
 241         </td></tr><tr><td><code class="literal">ISO_8859_8</code></td><td><span class="emphasis"><em>ISO_8859_8</em></span>,
 242         <code class="literal">UTF8</code>
 243         </td></tr><tr><td><code class="literal">JOHAB</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 244         </td></tr><tr><td><code class="literal">KOI8R</code></td><td><span class="emphasis"><em>KOI8R</em></span>,
 245         <code class="literal">ISO_8859_5</code>,
 246         <code class="literal">MULE_INTERNAL</code>,
 247         <code class="literal">UTF8</code>,
 248         <code class="literal">WIN866</code>,
 249         <code class="literal">WIN1251</code>
 250         </td></tr><tr><td><code class="literal">KOI8U</code></td><td><span class="emphasis"><em>KOI8U</em></span>,
 251         <code class="literal">UTF8</code>
 252         </td></tr><tr><td><code class="literal">LATIN1</code></td><td><span class="emphasis"><em>LATIN1</em></span>,
 253         <code class="literal">MULE_INTERNAL</code>,
 254         <code class="literal">UTF8</code>
 255         </td></tr><tr><td><code class="literal">LATIN2</code></td><td><span class="emphasis"><em>LATIN2</em></span>,
 256         <code class="literal">MULE_INTERNAL</code>,
 257         <code class="literal">UTF8</code>,
 258         <code class="literal">WIN1250</code>
 259         </td></tr><tr><td><code class="literal">LATIN3</code></td><td><span class="emphasis"><em>LATIN3</em></span>,
 260         <code class="literal">MULE_INTERNAL</code>,
 261         <code class="literal">UTF8</code>
 262         </td></tr><tr><td><code class="literal">LATIN4</code></td><td><span class="emphasis"><em>LATIN4</em></span>,
 263         <code class="literal">MULE_INTERNAL</code>,
 264         <code class="literal">UTF8</code>
 265         </td></tr><tr><td><code class="literal">LATIN5</code></td><td><span class="emphasis"><em>LATIN5</em></span>,
 266         <code class="literal">UTF8</code>
 267         </td></tr><tr><td><code class="literal">LATIN6</code></td><td><span class="emphasis"><em>LATIN6</em></span>,
 268         <code class="literal">UTF8</code>
 269         </td></tr><tr><td><code class="literal">LATIN7</code></td><td><span class="emphasis"><em>LATIN7</em></span>,
 270         <code class="literal">UTF8</code>
 271         </td></tr><tr><td><code class="literal">LATIN8</code></td><td><span class="emphasis"><em>LATIN8</em></span>,
 272         <code class="literal">UTF8</code>
 273         </td></tr><tr><td><code class="literal">LATIN9</code></td><td><span class="emphasis"><em>LATIN9</em></span>,
 274         <code class="literal">UTF8</code>
 275         </td></tr><tr><td><code class="literal">LATIN10</code></td><td><span class="emphasis"><em>LATIN10</em></span>,
 276         <code class="literal">UTF8</code>
 277         </td></tr><tr><td><code class="literal">MULE_INTERNAL</code></td><td><span class="emphasis"><em>MULE_INTERNAL</em></span>,
 278          <code class="literal">BIG5</code>,
 279          <code class="literal">EUC_CN</code>,
 280          <code class="literal">EUC_JP</code>,
 281          <code class="literal">EUC_KR</code>,
 282          <code class="literal">EUC_TW</code>,
 283          <code class="literal">ISO_8859_5</code>,
 284          <code class="literal">KOI8R</code>,
 285          <code class="literal">LATIN1</code> to <code class="literal">LATIN4</code>,
 286          <code class="literal">SJIS</code>,
 287          <code class="literal">WIN866</code>,
 288          <code class="literal">WIN1250</code>,
 289          <code class="literal">WIN1251</code>
 290         </td></tr><tr><td><code class="literal">SJIS</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 291         </td></tr><tr><td><code class="literal">SHIFT_JIS_2004</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 292         </td></tr><tr><td><code class="literal">SQL_ASCII</code></td><td><span class="emphasis"><em>any (no conversion will be performed)</em></span>
 293         </td></tr><tr><td><code class="literal">UHC</code></td><td><span class="emphasis"><em>not supported as a server encoding</em></span>
 294         </td></tr><tr><td><code class="literal">UTF8</code></td><td><span class="emphasis"><em>all supported encodings</em></span>
 295         </td></tr><tr><td><code class="literal">WIN866</code></td><td><span class="emphasis"><em>WIN866</em></span>,
 296          <code class="literal">ISO_8859_5</code>,
 297          <code class="literal">KOI8R</code>,
 298          <code class="literal">MULE_INTERNAL</code>,
 299          <code class="literal">UTF8</code>,
 300          <code class="literal">WIN1251</code>
 301         </td></tr><tr><td><code class="literal">WIN874</code></td><td><span class="emphasis"><em>WIN874</em></span>,
 302         <code class="literal">UTF8</code>
 303         </td></tr><tr><td><code class="literal">WIN1250</code></td><td><span class="emphasis"><em>WIN1250</em></span>,
 304          <code class="literal">LATIN2</code>,
 305          <code class="literal">MULE_INTERNAL</code>,
 306          <code class="literal">UTF8</code>
 307         </td></tr><tr><td><code class="literal">WIN1251</code></td><td><span class="emphasis"><em>WIN1251</em></span>,
 308          <code class="literal">ISO_8859_5</code>,
 309          <code class="literal">KOI8R</code>,
 310          <code class="literal">MULE_INTERNAL</code>,
 311          <code class="literal">UTF8</code>,
 312          <code class="literal">WIN866</code>
 313         </td></tr><tr><td><code class="literal">WIN1252</code></td><td><span class="emphasis"><em>WIN1252</em></span>,
 314          <code class="literal">UTF8</code>
 315         </td></tr><tr><td><code class="literal">WIN1253</code></td><td><span class="emphasis"><em>WIN1253</em></span>,
 316          <code class="literal">UTF8</code>
 317         </td></tr><tr><td><code class="literal">WIN1254</code></td><td><span class="emphasis"><em>WIN1254</em></span>,
 318          <code class="literal">UTF8</code>
 319         </td></tr><tr><td><code class="literal">WIN1255</code></td><td><span class="emphasis"><em>WIN1255</em></span>,
 320          <code class="literal">UTF8</code>
 321         </td></tr><tr><td><code class="literal">WIN1256</code></td><td><span class="emphasis"><em>WIN1256</em></span>,
 322         <code class="literal">UTF8</code>
 323         </td></tr><tr><td><code class="literal">WIN1257</code></td><td><span class="emphasis"><em>WIN1257</em></span>,
 324          <code class="literal">UTF8</code>
 325         </td></tr><tr><td><code class="literal">WIN1258</code></td><td><span class="emphasis"><em>WIN1258</em></span>,
 326         <code class="literal">UTF8</code>
 327         </td></tr></tbody></table></div></div><br class="table-break" /><div class="table" id="BUILTIN-CONVERSIONS-TABLE"><p class="title"><strong>Table 23.5. All Built-in Character Set Conversions</strong></p><div class="table-contents"><table class="table" summary="All Built-in Character Set Conversions" border="1"><colgroup><col class="col1" /><col class="col2" /><col class="col3" /></colgroup><thead><tr><th>Conversion Name
 328          <a href="#ftn.id-1.6.10.5.8.4.2.4.1.1.1" class="footnote"><sup class="footnote" id="id-1.6.10.5.8.4.2.4.1.1.1">[a]</sup></a>
 329         </th><th>Source Encoding</th><th>Destination Encoding</th></tr></thead><tbody><tr><td><code class="literal">big5_to_euc_tw</code></td><td><code class="literal">BIG5</code></td><td><code class="literal">EUC_TW</code></td></tr><tr><td><code class="literal">big5_to_mic</code></td><td><code class="literal">BIG5</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">big5_to_utf8</code></td><td><code class="literal">BIG5</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">euc_cn_to_mic</code></td><td><code class="literal">EUC_CN</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">euc_cn_to_utf8</code></td><td><code class="literal">EUC_CN</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">euc_jp_to_mic</code></td><td><code class="literal">EUC_JP</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">euc_jp_to_sjis</code></td><td><code class="literal">EUC_JP</code></td><td><code class="literal">SJIS</code></td></tr><tr><td><code class="literal">euc_jp_to_utf8</code></td><td><code class="literal">EUC_JP</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">euc_kr_to_mic</code></td><td><code class="literal">EUC_KR</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">euc_kr_to_utf8</code></td><td><code class="literal">EUC_KR</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">euc_tw_to_big5</code></td><td><code class="literal">EUC_TW</code></td><td><code class="literal">BIG5</code></td></tr><tr><td><code class="literal">euc_tw_to_mic</code></td><td><code class="literal">EUC_TW</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">euc_tw_to_utf8</code></td><td><code class="literal">EUC_TW</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">gb18030_to_utf8</code></td><td><code class="literal">GB18030</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">gbk_to_utf8</code></td><td><code class="literal">GBK</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_10_to_utf8</code></td><td><code class="literal">LATIN6</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_13_to_utf8</code></td><td><code class="literal">LATIN7</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_14_to_utf8</code></td><td><code class="literal">LATIN8</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_15_to_utf8</code></td><td><code class="literal">LATIN9</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_16_to_utf8</code></td><td><code class="literal">LATIN10</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_1_to_mic</code></td><td><code class="literal">LATIN1</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">iso_8859_1_to_utf8</code></td><td><code class="literal">LATIN1</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_2_to_mic</code></td><td><code class="literal">LATIN2</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">iso_8859_2_to_utf8</code></td><td><code class="literal">LATIN2</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_2_to_windows_1250</code></td><td><code class="literal">LATIN2</code></td><td><code class="literal">WIN1250</code></td></tr><tr><td><code class="literal">iso_8859_3_to_mic</code></td><td><code class="literal">LATIN3</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">iso_8859_3_to_utf8</code></td><td><code class="literal">LATIN3</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_4_to_mic</code></td><td><code class="literal">LATIN4</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">iso_8859_4_to_utf8</code></td><td><code class="literal">LATIN4</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_5_to_koi8_r</code></td><td><code class="literal">ISO_8859_5</code></td><td><code class="literal">KOI8R</code></td></tr><tr><td><code class="literal">iso_8859_5_to_mic</code></td><td><code class="literal">ISO_8859_5</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">iso_8859_5_to_utf8</code></td><td><code class="literal">ISO_8859_5</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_5_to_windows_1251</code></td><td><code class="literal">ISO_8859_5</code></td><td><code class="literal">WIN1251</code></td></tr><tr><td><code class="literal">iso_8859_5_to_windows_866</code></td><td><code class="literal">ISO_8859_5</code></td><td><code class="literal">WIN866</code></td></tr><tr><td><code class="literal">iso_8859_6_to_utf8</code></td><td><code class="literal">ISO_8859_6</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_7_to_utf8</code></td><td><code class="literal">ISO_8859_7</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_8_to_utf8</code></td><td><code class="literal">ISO_8859_8</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">iso_8859_9_to_utf8</code></td><td><code class="literal">LATIN5</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">johab_to_utf8</code></td><td><code class="literal">JOHAB</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">koi8_r_to_iso_8859_5</code></td><td><code class="literal">KOI8R</code></td><td><code class="literal">ISO_8859_5</code></td></tr><tr><td><code class="literal">koi8_r_to_mic</code></td><td><code class="literal">KOI8R</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">koi8_r_to_utf8</code></td><td><code class="literal">KOI8R</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">koi8_r_to_windows_1251</code></td><td><code class="literal">KOI8R</code></td><td><code class="literal">WIN1251</code></td></tr><tr><td><code class="literal">koi8_r_to_windows_866</code></td><td><code class="literal">KOI8R</code></td><td><code class="literal">WIN866</code></td></tr><tr><td><code class="literal">koi8_u_to_utf8</code></td><td><code class="literal">KOI8U</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">mic_to_big5</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">BIG5</code></td></tr><tr><td><code class="literal">mic_to_euc_cn</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">EUC_CN</code></td></tr><tr><td><code class="literal">mic_to_euc_jp</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">EUC_JP</code></td></tr><tr><td><code class="literal">mic_to_euc_kr</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">EUC_KR</code></td></tr><tr><td><code class="literal">mic_to_euc_tw</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">EUC_TW</code></td></tr><tr><td><code class="literal">mic_to_iso_8859_1</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">LATIN1</code></td></tr><tr><td><code class="literal">mic_to_iso_8859_2</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">LATIN2</code></td></tr><tr><td><code class="literal">mic_to_iso_8859_3</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">LATIN3</code></td></tr><tr><td><code class="literal">mic_to_iso_8859_4</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">LATIN4</code></td></tr><tr><td><code class="literal">mic_to_iso_8859_5</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">ISO_8859_5</code></td></tr><tr><td><code class="literal">mic_to_koi8_r</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">KOI8R</code></td></tr><tr><td><code class="literal">mic_to_sjis</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">SJIS</code></td></tr><tr><td><code class="literal">mic_to_windows_1250</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">WIN1250</code></td></tr><tr><td><code class="literal">mic_to_windows_1251</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">WIN1251</code></td></tr><tr><td><code class="literal">mic_to_windows_866</code></td><td><code class="literal">MULE_INTERNAL</code></td><td><code class="literal">WIN866</code></td></tr><tr><td><code class="literal">sjis_to_euc_jp</code></td><td><code class="literal">SJIS</code></td><td><code class="literal">EUC_JP</code></td></tr><tr><td><code class="literal">sjis_to_mic</code></td><td><code class="literal">SJIS</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">sjis_to_utf8</code></td><td><code class="literal">SJIS</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">windows_1258_to_utf8</code></td><td><code class="literal">WIN1258</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">uhc_to_utf8</code></td><td><code class="literal">UHC</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">utf8_to_big5</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">BIG5</code></td></tr><tr><td><code class="literal">utf8_to_euc_cn</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">EUC_CN</code></td></tr><tr><td><code class="literal">utf8_to_euc_jp</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">EUC_JP</code></td></tr><tr><td><code class="literal">utf8_to_euc_kr</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">EUC_KR</code></td></tr><tr><td><code class="literal">utf8_to_euc_tw</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">EUC_TW</code></td></tr><tr><td><code class="literal">utf8_to_gb18030</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">GB18030</code></td></tr><tr><td><code class="literal">utf8_to_gbk</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">GBK</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_1</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN1</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_10</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN6</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_13</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN7</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_14</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN8</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_15</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN9</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_16</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN10</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_2</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN2</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_3</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN3</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_4</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN4</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_5</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">ISO_8859_5</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_6</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">ISO_8859_6</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_7</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">ISO_8859_7</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_8</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">ISO_8859_8</code></td></tr><tr><td><code class="literal">utf8_to_iso_8859_9</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">LATIN5</code></td></tr><tr><td><code class="literal">utf8_to_johab</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">JOHAB</code></td></tr><tr><td><code class="literal">utf8_to_koi8_r</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">KOI8R</code></td></tr><tr><td><code class="literal">utf8_to_koi8_u</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">KOI8U</code></td></tr><tr><td><code class="literal">utf8_to_sjis</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">SJIS</code></td></tr><tr><td><code class="literal">utf8_to_windows_1258</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1258</code></td></tr><tr><td><code class="literal">utf8_to_uhc</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">UHC</code></td></tr><tr><td><code class="literal">utf8_to_windows_1250</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1250</code></td></tr><tr><td><code class="literal">utf8_to_windows_1251</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1251</code></td></tr><tr><td><code class="literal">utf8_to_windows_1252</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1252</code></td></tr><tr><td><code class="literal">utf8_to_windows_1253</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1253</code></td></tr><tr><td><code class="literal">utf8_to_windows_1254</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1254</code></td></tr><tr><td><code class="literal">utf8_to_windows_1255</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1255</code></td></tr><tr><td><code class="literal">utf8_to_windows_1256</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1256</code></td></tr><tr><td><code class="literal">utf8_to_windows_1257</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN1257</code></td></tr><tr><td><code class="literal">utf8_to_windows_866</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN866</code></td></tr><tr><td><code class="literal">utf8_to_windows_874</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">WIN874</code></td></tr><tr><td><code class="literal">windows_1250_to_iso_8859_2</code></td><td><code class="literal">WIN1250</code></td><td><code class="literal">LATIN2</code></td></tr><tr><td><code class="literal">windows_1250_to_mic</code></td><td><code class="literal">WIN1250</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">windows_1250_to_utf8</code></td><td><code class="literal">WIN1250</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">windows_1251_to_iso_8859_5</code></td><td><code class="literal">WIN1251</code></td><td><code class="literal">ISO_8859_5</code></td></tr><tr><td><code class="literal">windows_1251_to_koi8_r</code></td><td><code class="literal">WIN1251</code></td><td><code class="literal">KOI8R</code></td></tr><tr><td><code class="literal">windows_1251_to_mic</code></td><td><code class="literal">WIN1251</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">windows_1251_to_utf8</code></td><td><code class="literal">WIN1251</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">windows_1251_to_windows_866</code></td><td><code class="literal">WIN1251</code></td><td><code class="literal">WIN866</code></td></tr><tr><td><code class="literal">windows_1252_to_utf8</code></td><td><code class="literal">WIN1252</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">windows_1256_to_utf8</code></td><td><code class="literal">WIN1256</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">windows_866_to_iso_8859_5</code></td><td><code class="literal">WIN866</code></td><td><code class="literal">ISO_8859_5</code></td></tr><tr><td><code class="literal">windows_866_to_koi8_r</code></td><td><code class="literal">WIN866</code></td><td><code class="literal">KOI8R</code></td></tr><tr><td><code class="literal">windows_866_to_mic</code></td><td><code class="literal">WIN866</code></td><td><code class="literal">MULE_INTERNAL</code></td></tr><tr><td><code class="literal">windows_866_to_utf8</code></td><td><code class="literal">WIN866</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">windows_866_to_windows_1251</code></td><td><code class="literal">WIN866</code></td><td><code class="literal">WIN</code></td></tr><tr><td><code class="literal">windows_874_to_utf8</code></td><td><code class="literal">WIN874</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">euc_jis_2004_to_utf8</code></td><td><code class="literal">EUC_JIS_2004</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">utf8_to_euc_jis_2004</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">EUC_JIS_2004</code></td></tr><tr><td><code class="literal">shift_jis_2004_to_utf8</code></td><td><code class="literal">SHIFT_JIS_2004</code></td><td><code class="literal">UTF8</code></td></tr><tr><td><code class="literal">utf8_to_shift_jis_2004</code></td><td><code class="literal">UTF8</code></td><td><code class="literal">SHIFT_JIS_2004</code></td></tr><tr><td><code class="literal">euc_jis_2004_to_shift_jis_2004</code></td><td><code class="literal">EUC_JIS_2004</code></td><td><code class="literal">SHIFT_JIS_2004</code></td></tr><tr><td><code class="literal">shift_jis_2004_to_euc_jis_2004</code></td><td><code class="literal">SHIFT_JIS_2004</code></td><td><code class="literal">EUC_JIS_2004</code></td></tr></tbody><tbody class="footnotes"><tr><td colspan="3"><div id="ftn.id-1.6.10.5.8.4.2.4.1.1.1" class="footnote"><p><a href="#id-1.6.10.5.8.4.2.4.1.1.1" class="para"><sup class="para">[a] </sup></a>
 330            The conversion names follow a standard naming scheme: The
 331            official name of the source encoding with all
 332            non-alphanumeric characters replaced by underscores, followed
 333            by <code class="literal">_to_</code>, followed by the similarly processed
 334            destination encoding name.  Therefore, these names sometimes
 335            deviate from the customary encoding names shown in
 336            <a class="xref" href="multibyte.html#CHARSET-TABLE" title="Table 23.3. PostgreSQL Character Sets">Table 23.3</a>.
 337           </p></div></td></tr></tbody></table></div></div><br class="table-break" /></div><div class="sect2" id="MULTIBYTE-FURTHER-READING"><div class="titlepage"><div><div><h3 class="title">23.3.5. Further Reading <a href="#MULTIBYTE-FURTHER-READING" class="id_link">#</a></h3></div></div></div><p>
 338      These are good sources to start learning about various kinds of encoding
 339      systems.
 340
 341      </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="citetitle">CJKV Information Processing: Chinese, Japanese, Korean &amp; Vietnamese Computing</em></span></dt><dd><p>
 342          Contains detailed explanations of <code class="literal">EUC_JP</code>,
 343          <code class="literal">EUC_CN</code>, <code class="literal">EUC_KR</code>,
 344          <code class="literal">EUC_TW</code>.
 345         </p></dd><dt><span class="term"><a class="ulink" href="https://www.unicode.org/" target="_top">https://www.unicode.org/</a></span></dt><dd><p>
 346          The web site of the Unicode Consortium.
 347         </p></dd><dt><span class="term"><a class="ulink" href="https://datatracker.ietf.org/doc/html/rfc3629" target="_top">RFC 3629</a></span></dt><dd><p>
 348          <acronym class="acronym">UTF</acronym>-8 (8-bit UCS/Unicode Transformation
 349          Format) is defined here.
 350         </p></dd></dl></div><p>
 351     </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="collation.html" title="23.2. Collation Support">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="charset.html" title="Chapter 23. Localization">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="maintenance.html" title="Chapter 24. Routine Database Maintenance Tasks">Next</a></td></tr><tr><td width="40%" align="left" valign="top">23.2. Collation Support </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="40%" align="right" valign="top"> Chapter 24. Routine Database Maintenance Tasks</td></tr></table></div></body></html>