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0a3142725875ea286597e083547d34d98f8c1f2drbowen<p class="menu"><a href="/mod/">Modules</a> | <a href="/mod/directives.html">Directives</a> | <a href="/faq/">FAQ</a> | <a href="/glossary.html">Glossary</a> | <a href="/sitemap.html">Sitemap</a></p>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<div class="up"><a href="./"><img title="<-" alt="<-" src="/images/left.gif" /></a></div>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.3</a> > <a href="./">Rewrite</a></div><div id="page-content"><div id="preamble"><h1>Using RewriteMap</h1>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<p><span>Available Languages: </span><a href="/en/rewrite/rewritemap.html" title="English"> en </a></p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>This document supplements the <code class="module"><a href="/mod/mod_rewrite.html">mod_rewrite</a></code>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<a href="/mod/mod_rewrite.html">reference documentation</a>. It describes
0a3142725875ea286597e083547d34d98f8c1f2drbowenthe use of the <code class="directive"><a href="/mod/mod_rewrite.html#rewritemap">RewriteMap</a></code> directive,
0a3142725875ea286597e083547d34d98f8c1f2drbowenand provides examples of each of the various <code>RewriteMap</code> types.</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <div class="warning">Note that many of these examples won't work unchanged in your
0a3142725875ea286597e083547d34d98f8c1f2drbowenparticular server configuration, so it's important that you understand
0a3142725875ea286597e083547d34d98f8c1f2drbowenthem, rather than merely cutting and pasting the examples into your
0a3142725875ea286597e083547d34d98f8c1f2drbowenconfiguration.</div>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<div id="quickview"><ul id="toc"><li><img alt="" src="/images/down.gif" /> <a href="#introduction">Introduction</a></li>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<li><img alt="" src="/images/down.gif" /> <a href="#txt">txt: Plain text maps</a></li>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<li><img alt="" src="/images/down.gif" /> <a href="#rnd">rnd: Randomized Plain Text</a></li>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<li><img alt="" src="/images/down.gif" /> <a href="#dbm">dbm: DBM Hash File</a></li>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<li><img alt="" src="/images/down.gif" /> <a href="#int">int: Internal Function</a></li>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<li><img alt="" src="/images/down.gif" /> <a href="#prg">prg: External Rewriting Program</a></li>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<li><img alt="" src="/images/down.gif" /> <a href="#dbd">dbd or fastdbd: SQL Query</a></li>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<li><img alt="" src="/images/down.gif" /> <a href="#summary">Summary</a></li>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen</ul><h3>See also</h3><ul class="seealso"><li><a href="/mod/mod_rewrite.html">Module documentation</a></li><li><a href="intro.html">mod_rewrite introduction</a></li><li><a href="remapping.html">Redirection and remapping</a></li><li><a href="access.html">Controlling access</a></li><li><a href="vhosts.html">Virtual hosts</a></li><li><a href="proxy.html">Proxying</a></li><li><a href="advanced.html">Advanced techniques and tricks</a></li><li><a href="avoid.html">When not to use mod_rewrite</a></li></ul></div>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<h2><a name="introduction" id="introduction">Introduction</a></h2>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen The <code class="directive"><a href="/mod/mod_rewrite.html#rewritemap">RewriteMap</a></code> directive
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen defines an external function which can be called in the context of
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <code class="directive"><a href="/mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> or
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <code class="directive"><a href="/mod/mod_rewrite.html#rewritecond">RewriteCond</a></code> directives to
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen perform rewriting that is too complicated, or too specialized to be
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen performed just by regular expressions. The source of this lookup can
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen be any of the types listed in the sections below, and enumerated in
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen the <code class="directive"><a href="/mod/mod_rewrite.html#rewritemap">RewriteMap</a></code> reference
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen documentation.</p>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <p>The syntax of the <code>RewriteMap</code> directive is as
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen follows:</p>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenRewriteMap <em>MapName</em> <em>MapType</em>:<em>MapSource</em>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <p>The <a id="mapfunc" name="mapfunc"><em>MapName</em></a> is an
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen arbitray name that you assign to the map, and which you will use in
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen directives later on. Arguments are passed to the map via the
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen following syntax:</p>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <code>${</code> <em>MapName</em> <code>:</code> <em>LookupKey</em>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <code>}</code> <br /> <code>${</code> <em>MapName</em> <code>:</code>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen <em>LookupKey</em> <code>|</code> <em>DefaultValue</em> <code>}</code>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>When such a construct occurs, the map <em>MapName</em> is
0a3142725875ea286597e083547d34d98f8c1f2drbowen consulted and the key <em>LookupKey</em> is looked-up. If the
0a3142725875ea286597e083547d34d98f8c1f2drbowen key is found, the map-function construct is substituted by
0a3142725875ea286597e083547d34d98f8c1f2drbowen <em>SubstValue</em>. If the key is not found then it is
0a3142725875ea286597e083547d34d98f8c1f2drbowen substituted by <em>DefaultValue</em> or by the empty string
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>For example, you might define a
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>You would then be able to use this map in a
0a3142725875ea286597e083547d34d98f8c1f2drbowen <code class="directive">RewriteRule</code> as follows:</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen RewriteRule ^/ex/(.*) ${examplemap:$1}
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen<p>A default value can be specified in the event that nothing is found
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowenin the map:</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowenRewriteRule ^/ex/(.*) ${examplemap:$1|/not_found.html}
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen<p>The sections that follow describe the various <em>MapType</em>s that
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenmay be used, and give examples of each.</p>
0a3142725875ea286597e083547d34d98f8c1f2drbowen </div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<h2><a name="txt" id="txt">txt: Plain text maps</a></h2>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>When a MapType of <code>txt</code>is used, the MapSource is a filesystem path to a
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen plain-text mapping file, containing space-separated key/value pair
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen per line. Optionally, a line may be contain a comment, starting with
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen a '#' character.</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>For example, the following might be valid entries in a map
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen # Comment line
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <strong><em>MatchingKey</em> <em>SubstValue</em></strong><br />
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <strong><em>MatchingKey</em> <em>SubstValue</em></strong> # comment<br />
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>When the RewriteMap is invoked the argument is looked for in the
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen first argument of a line, and, if found, the substitution value is
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen returned.</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>For example, we might use a mapfile to translate product names to
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen product IDs for easier-to-remember URLs, using the following
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen recipe:</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <div class="example"><h3>Product to ID configuration</h3><p><code>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen RewriteMap product2id txt:/etc/apache2/productmap.txt<br />
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen RewriteRule ^/product/(.*) /prods.php?id=${product2id:$1|NOTFOUND} [PT]
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>We assume here that the <code>prods.php</code> script knows what
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen to do when it received an argument of <code>id=NOTFOUND</code> when
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen a product is not found in the lookup map.</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>The file <code>/etc/apache2/productmap.txt</code> then contains
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen the following:</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen## productmap.txt - Product to ID map file
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowentelevision 993
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowenfishingrod 043
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowenbasketball 418
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowentelephone 328
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen <p>Thus, when <code>http://example.com/product/television</code> is
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen requested, the <code>RewriteRule</code> is applied, and the request
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen is internally mapped to <code>/prods.php?id=993</code>.</p>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen The example given is crafted to be used in server or virtualhost
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen scope. If you're planning to use this in a <code>.htaccess</code>
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen file, you'll need to remove the leading slash from the rewrite
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen pattern in order for it to match anything:
721755eb7ca9b3bf233f223d48e43edd7795c6ebrbowen RewriteRule ^product/(.*) /prods.php?id=${product2id:$1|NOTFOUND} [PT]
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen </div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<h2><a name="rnd" id="rnd">rnd: Randomized Plain Text</a></h2>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>MapType: <code>rnd</code>, MapSource: Unix filesystem
0a3142725875ea286597e083547d34d98f8c1f2drbowen path to valid regular file</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>This is identical to the Standard Plain Text variant
0a3142725875ea286597e083547d34d98f8c1f2drbowen above but with a special post-processing feature: After
0a3142725875ea286597e083547d34d98f8c1f2drbowen looking up a value it is parsed according to contained
0a3142725875ea286597e083547d34d98f8c1f2drbowen ``<code>|</code>'' characters which have the meaning of
0a3142725875ea286597e083547d34d98f8c1f2drbowen ``or''. In other words they indicate a set of
0a3142725875ea286597e083547d34d98f8c1f2drbowen alternatives from which the actual returned value is
0a3142725875ea286597e083547d34d98f8c1f2drbowen chosen randomly. For example, you might use the following map
0a3142725875ea286597e083547d34d98f8c1f2drbowen file and directives to provide a random load balancing between
0a3142725875ea286597e083547d34d98f8c1f2drbowen several back-end server, via a reverse-proxy. Images are sent
0a3142725875ea286597e083547d34d98f8c1f2drbowen to one of the servers in the 'static' pool, while everything
0a3142725875ea286597e083547d34d98f8c1f2drbowen else is sent to one of the 'dynamic' pool.</p>
0a3142725875ea286597e083547d34d98f8c1f2drbowen## map.txt -- rewriting map
0a3142725875ea286597e083547d34d98f8c1f2drbowenstatic www1|www2|www3|www4
0a3142725875ea286597e083547d34d98f8c1f2drbowendynamic www5|www6
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <div class="example"><h3>Configuration directives</h3><p><code>
0a3142725875ea286597e083547d34d98f8c1f2drbowenRewriteRule ^/(.*\.(png|gif|jpg)) http://${servers:static}/$1
0a3142725875ea286597e083547d34d98f8c1f2drbowen[NC,P,L]<br />
0a3142725875ea286597e083547d34d98f8c1f2drbowenRewriteRule ^/(.*) http://${servers:dynamic}/$1 [P,L]
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen </div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<h2><a name="dbm" id="dbm">dbm: DBM Hash File</a></h2>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>MapType:
0a3142725875ea286597e083547d34d98f8c1f2drbowen <code>dbm[=<em>type</em>]</code>, MapSource: Unix filesystem
0a3142725875ea286597e083547d34d98f8c1f2drbowen path to valid regular file</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>Here the source is a binary format DBM file containing
0a3142725875ea286597e083547d34d98f8c1f2drbowen the same contents as a <em>Plain Text</em> format file, but
0a3142725875ea286597e083547d34d98f8c1f2drbowen in a special representation which is optimized for really
0a3142725875ea286597e083547d34d98f8c1f2drbowen fast lookups. The <em>type</em> can be sdbm, gdbm, ndbm, or
0a3142725875ea286597e083547d34d98f8c1f2drbowen db depending on <a href="/install.html#dbm">compile-time
0a3142725875ea286597e083547d34d98f8c1f2drbowen compile-time default will be chosen.</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>To create a dbm file from a source text file, use the <a href="/programs/httxt2dbm.html">httxt2dbm</a> utility.</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen </div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<h2><a name="int" id="int">int: Internal Function</a></h2>
0a3142725875ea286597e083547d34d98f8c1f2drbowen MapType: <code>int</code>, MapSource: Internal Apache httpd
0a3142725875ea286597e083547d34d98f8c1f2drbowen function</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>Here, the source is an internal Apache httpd function.
0a3142725875ea286597e083547d34d98f8c1f2drbowen Currently you cannot create your own, but the following
0a3142725875ea286597e083547d34d98f8c1f2drbowen functions already exist:</p>
0a3142725875ea286597e083547d34d98f8c1f2drbowen Converts the key to all upper case.</li>
0a3142725875ea286597e083547d34d98f8c1f2drbowen Converts the key to all lower case.</li>
0a3142725875ea286597e083547d34d98f8c1f2drbowen Translates special characters in the key to
0a3142725875ea286597e083547d34d98f8c1f2drbowen hex-encodings.</li>
0a3142725875ea286597e083547d34d98f8c1f2drbowen Translates hex-encodings in the key back to
0a3142725875ea286597e083547d34d98f8c1f2drbowen special characters.</li>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen </div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen<h2><a name="prg" id="prg">prg: External Rewriting Program</a></h2>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen<p>MapType: <code>prg</code>, MapSource: Unix filesystem path to valid regular file </p>
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen<p>Here the source is a program, not a map file. To
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowencreate it you can use a language of your choice, but
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenthe result has to be an executable program (either
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenobject-code or a script with the magic cookie trick
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenline).</p><p>This program is started once, when the Apache httpd server
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenis started, and then communicates with the rewriting engine
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenfile-handles. For each map-function lookup it will
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenreceive the key to lookup as a newline-terminated string
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenlooked-up value as a newline-terminated string on
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen``<code>NULL</code>'' if it fails (<em>i.e.</em>, there
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenis no corresponding value for the given key).</p><p>This feature utilizes the <code>rewrite-map</code> mutex,
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenwhich is required for reliable communication with the program.
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowenThe mutex mechanism and lock file can be configured with the
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowen<code class="directive"><a href="/mod/core.html#mutex">Mutex</a></code> directive.</p><p>External rewriting programs are not started if they're defined in a
83f3471f5de14ca3def6d7935cd1af1604874bfdrbowencontext that does not have <code class="directive">RewriteEngine</code> set to
0a3142725875ea286597e083547d34d98f8c1f2drbowen <p>A trivial program which will implement a 1:1 map (<em>i.e.</em>,
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen key == value) could be:</p><div class="example"><pre>
0a3142725875ea286597e083547d34d98f8c1f2drbowenwhile (<STDIN>) {
0a3142725875ea286597e083547d34d98f8c1f2drbowen # ...put here any transformations or lookups...
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen</pre></div><p>But be very careful:</p><ol><li>``<em>Keep it simple, stupid</em>'' (KISS).
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenIf this program hangs, it will cause Apache httpd to hang
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenwhen trying to use the relevant rewrite rule.</li><li>A common mistake is to use buffered I/O on
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<code>stdout</code>. Avoid this, as it will cause a deadloop!
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen``<code>$|=1</code>'' is used above, to prevent this.</li></ol></div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<h2><a name="dbd" id="dbd">dbd or fastdbd: SQL Query</a></h2>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>MapType: <code>dbd</code> or <code>fastdbd</code>,
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenMapSource: An SQL SELECT statement that takes a single
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen argument and returns a single value.</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>This uses <code class="module"><a href="/mod/mod_dbd.html">mod_dbd</a></code> to implement a rewritemap
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenby lookup in an SQL database. There are two forms:
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<code>fastdbd</code> caches database lookups internally,
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen<code>dbd</code> doesn't. So <code>dbd</code> incurs a
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenperformance penalty but responds immediately if the database
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowencontents are updated, while <code>fastdbd</code> is more
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenefficient but won't re-read database contents until server
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenrestart.</p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>If a query returns more than one row, a random row from
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowenthe result set is used.</p>
0a3142725875ea286597e083547d34d98f8c1f2drbowenRewriteMap myquery "fastdbd:SELECT destination FROM rewrite WHERE source = %s"
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen </div><div class="top"><a href="#page-header"><img alt="top" src="/images/up.gif" /></a></div>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <p>The <code class="directive">RewriteMap</code> directive can occur more than
0a3142725875ea286597e083547d34d98f8c1f2drbowen once. For each mapping-function use one
0a3142725875ea286597e083547d34d98f8c1f2drbowen <code class="directive">RewriteMap</code> directive to declare its rewriting
0a3142725875ea286597e083547d34d98f8c1f2drbowen mapfile. While you cannot <strong>declare</strong> a map in
0a3142725875ea286597e083547d34d98f8c1f2drbowen per-directory context it is of course possible to
0a3142725875ea286597e083547d34d98f8c1f2drbowen <strong>use</strong> this map in per-directory context. </p>
cde7900bb5b14f5bd981ad98b0215c85b915bef7rbowen <div class="note"><h3>Note</h3> For plain text and DBM format files the
0a3142725875ea286597e083547d34d98f8c1f2drbowenlooked-up keys are cached in-core until the <code>mtime</code> of the
0a3142725875ea286597e083547d34d98f8c1f2drbowenmapfile changes or the server does a restart. This way you can have
0a3142725875ea286597e083547d34d98f8c1f2drbowenmap-functions in rules which are used for <strong>every</strong>
0a3142725875ea286597e083547d34d98f8c1f2drbowenrequest. This is no problem, because the external lookup only happens
0a3142725875ea286597e083547d34d98f8c1f2drbowen<p><span>Available Languages: </span><a href="/en/rewrite/rewritemap.html" title="English"> en </a></p>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<p class="apache">Copyright 2010 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
0a3142725875ea286597e083547d34d98f8c1f2drbowen<p class="menu"><a href="/mod/">Modules</a> | <a href="/mod/directives.html">Directives</a> | <a href="/faq/">FAQ</a> | <a href="/glossary.html">Glossary</a> | <a href="/sitemap.html">Sitemap</a></p></div>