<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Execute operation with EXCLUSIVE LOCK</title>
</head>
<body><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="mysql-xdevapi-collectionfind.limit.html">CollectionFind::limit</a></div>
<div class="next" style="text-align: right; float: right;"><a href="mysql-xdevapi-collectionfind.lockshared.html">CollectionFind::lockShared</a></div>
<div class="up"><a href="class.mysql-xdevapi-collectionfind.html">mysql_xdevapi\CollectionFind</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div><hr /><div id="mysql-xdevapi-collectionfind.lockexclusive" class="refentry">
<div class="refnamediv">
<h1 class="refname">CollectionFind::lockExclusive</h1>
<p class="verinfo">(No version information available, might only be in Git)</p><p class="refpurpose"><span class="refname">CollectionFind::lockExclusive</span> — <span class="dc-title">Execute operation with EXCLUSIVE LOCK</span></p>
</div>
<div class="refsect1 description" id="refsect1-mysql-xdevapi-collectionfind.lockexclusive-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><span class="type mysql_xdevapi\CollectionFind">mysql_xdevapi\CollectionFind</span></span> <span class="methodname"><strong>mysql_xdevapi\CollectionFind::lockExclusive</strong></span>
([ <span class="methodparam"><span class="type">integer</span> <code class="parameter">$lock_waiting_option</code></span>
] )</div>
<p class="para rdfs-comment">
Lock exclusively the document, other transactions are blocked from updating the document until the document is locked
While the document is locked, other transactions are blocked from updating those docs, from doing SELECT ... LOCK IN SHARE MODE,
or from reading the data in certain transaction isolation levels. Consistent reads ignore any locks set on the records
that exist in the read view.
</p>
<p class="para">
This feature is directly useful with the modify() command, to avoid concurrency problems. Basically, it serializes access to a row through row locking
</p>
</div>
<div class="refsect1 parameters" id="refsect1-mysql-xdevapi-collectionfind.lockexclusive-parameters">
<h3 class="title">Parameters</h3>
<dl>
<dt>
<code class="parameter">lock_waiting_option</code></dt>
<dd>
<p class="para">
Optional waiting option. By default it is <strong><code>MYSQLX_LOCK_DEFAULT</code></strong>. Valid values are these constants:
</p>
<ul class="itemizedlist">
<li class="listitem"><p class="para"><strong><code>MYSQLX_LOCK_DEFAULT</code></strong></p></li>
<li class="listitem"><p class="para"><strong><code>MYSQLX_LOCK_NOWAIT</code></strong></p></li>
<li class="listitem"><p class="para"><strong><code>MYSQLX_LOCK_SKIP_LOCKED</code></strong></p></li>
</ul>
</dd>
</dl>
</div>
<div class="refsect1 returnvalues" id="refsect1-mysql-xdevapi-collectionfind.lockexclusive-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns a CollectionFind object that can be used for further processing
</p>
</div>
<div class="refsect1 examples" id="refsect1-mysql-xdevapi-collectionfind.lockexclusive-examples">
<h3 class="title">Examples</h3>
<div class="example" id="example-2004">
<p><strong>Example #1 <span class="function"><strong>mysql_xdevapi\CollectionFind::lockExclusive()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$session </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_xdevapi</span><span style="color: #007700">\</span><span style="color: #0000BB">getSession</span><span style="color: #007700">(</span><span style="color: #DD0000">"mysqlx://user:password@localhost"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$schema </span><span style="color: #007700">= </span><span style="color: #0000BB">$session</span><span style="color: #007700">-></span><span style="color: #0000BB">getSchema</span><span style="color: #007700">(</span><span style="color: #DD0000">"addressbook"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$collection </span><span style="color: #007700">= </span><span style="color: #0000BB">$schema</span><span style="color: #007700">-></span><span style="color: #0000BB">createCollection</span><span style="color: #007700">(</span><span style="color: #DD0000">"people"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$session</span><span style="color: #007700">-></span><span style="color: #0000BB">startTransaction</span><span style="color: #007700">();<br /><br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">$collection<br /> </span><span style="color: #007700">-></span><span style="color: #0000BB">find</span><span style="color: #007700">(</span><span style="color: #DD0000">"age > 50"</span><span style="color: #007700">)<br /> -></span><span style="color: #0000BB">lockExclusive</span><span style="color: #007700">()<br /> -></span><span style="color: #0000BB">execute</span><span style="color: #007700">();<br /><br /></span><span style="color: #FF8000">// ... do an operation on the object<br /><br />// Complete the transaction and unlock the document<br /></span><span style="color: #0000BB">$session</span><span style="color: #007700">-></span><span style="color: #0000BB">commit</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</div>
</div><hr /><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="mysql-xdevapi-collectionfind.limit.html">CollectionFind::limit</a></div>
<div class="next" style="text-align: right; float: right;"><a href="mysql-xdevapi-collectionfind.lockshared.html">CollectionFind::lockShared</a></div>
<div class="up"><a href="class.mysql-xdevapi-collectionfind.html">mysql_xdevapi\CollectionFind</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div></body></html>
