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| author | Timothy Warren <tim@timshomepage.net> | 2011-10-06 03:47:59 +0200 |
|---|---|---|
| committer | Timothy Warren <tim@timshomepage.net> | 2011-10-06 03:47:59 +0200 |
| commit | fb7ff742949e0474dfba30be45be513b3b4f63cc (patch) | |
| tree | 87b150fd502d0789f9660ca4dc2ace44817813c3 /user_guide/database/transactions.html | |
| parent | f7a8d86dbc6805a4e52964bbea76738df75b5f35 (diff) | |
| parent | ec8abee24f456b09ab9d53e88853fe6bd0f7879a (diff) | |
Merge branch 'develop' of git://github.com/EllisLab/CodeIgniter into develop
Diffstat (limited to 'user_guide/database/transactions.html')
| -rw-r--r-- | user_guide/database/transactions.html | 200 |
1 files changed, 0 insertions, 200 deletions
diff --git a/user_guide/database/transactions.html b/user_guide/database/transactions.html deleted file mode 100644 index 1a25f1657..000000000 --- a/user_guide/database/transactions.html +++ /dev/null @@ -1,200 +0,0 @@ -<!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" xml:lang="en" lang="en"> -<head> - -<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> -<title>Transactions : CodeIgniter User Guide</title> - -<style type='text/css' media='all'>@import url('../userguide.css');</style> -<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' /> - -<script type="text/javascript" src="../nav/nav.js"></script> -<script type="text/javascript" src="../nav/prototype.lite.js"></script> -<script type="text/javascript" src="../nav/moo.fx.js"></script> -<script type="text/javascript" src="../nav/user_guide_menu.js"></script> - -<meta http-equiv='expires' content='-1' /> -<meta http-equiv= 'pragma' content='no-cache' /> -<meta name='robots' content='all' /> -<meta name='author' content='ExpressionEngine Dev Team' /> -<meta name='description' content='CodeIgniter User Guide' /> - -</head> -<body> - -<!-- START NAVIGATION --> -<div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div> -<div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle_darker.jpg" width="154" height="43" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div> -<div id="masthead"> -<table cellpadding="0" cellspacing="0" border="0" style="width:100%"> -<tr> -<td><h1>CodeIgniter User Guide Version 2.0.3</h1></td> -<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td> -</tr> -</table> -</div> -<!-- END NAVIGATION --> - - - -<!-- START BREADCRUMB --> -<table cellpadding="0" cellspacing="0" border="0" style="width:100%"> -<tr> -<td id="breadcrumb"> -<a href="http://codeigniter.com/">CodeIgniter Home</a> › -<a href="../index.html">User Guide Home</a> › -<a href="index.html">Database Library</a> › -Transactions -</td> -<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="codeigniter.com/user_guide/" />Search User Guide <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" /> <input type="submit" class="submit" name="sa" value="Go" /></form></td> -</tr> -</table> -<!-- END BREADCRUMB --> - - -<br clear="all" /> - - -<!-- START CONTENT --> -<div id="content"> - - -<h1>Transactions</h1> - -<p>CodeIgniter's database abstraction allows you to use <dfn>transactions</dfn> with databases that support transaction-safe table types. In MySQL, you'll need -to be running InnoDB or BDB table types rather than the more common MyISAM. Most other database platforms support transactions natively.</p> - -<p>If you are not familiar with -transactions we recommend you find a good online resource to learn about them for your particular database. The information below assumes you -have a basic understanding of transactions. -</p> - -<h2>CodeIgniter's Approach to Transactions</h2> - -<p>CodeIgniter utilizes an approach to transactions that is very similar to the process used by the popular database class ADODB. We've chosen that approach -because it greatly simplifies the process of running transactions. In most cases all that is required are two lines of code.</p> - -<p>Traditionally, transactions have required a fair amount of work to implement since they demand that you to keep track of your queries -and determine whether to <dfn>commit</dfn> or <dfn>rollback</dfn> based on the success or failure of your queries. This is particularly cumbersome with -nested queries. In contrast, -we've implemented a smart transaction system that does all this for you automatically (you can also manage your transactions manually if you choose to, -but there's really no benefit).</p> - -<h2>Running Transactions</h2> - -<p>To run your queries using transactions you will use the <dfn>$this->db->trans_start()</dfn> and <dfn>$this->db->trans_complete()</dfn> functions as follows:</p> - -<code> -<kbd>$this->db->trans_start();</kbd><br /> -$this->db->query('AN SQL QUERY...');<br /> -$this->db->query('ANOTHER QUERY...');<br /> -$this->db->query('AND YET ANOTHER QUERY...');<br /> -<kbd>$this->db->trans_complete();</kbd> -</code> - -<p>You can run as many queries as you want between the start/complete functions and they will all be committed or rolled back based on success or failure -of any given query.</p> - - -<h2>Strict Mode</h2> - -<p>By default CodeIgniter runs all transactions in <dfn>Strict Mode</dfn>. When strict mode is enabled, if you are running multiple groups of -transactions, if one group fails all groups will be rolled back. If strict mode is disabled, each group is treated independently, meaning -a failure of one group will not affect any others.</p> - -<p>Strict Mode can be disabled as follows:</p> - -<code>$this->db->trans_strict(FALSE);</code> - - -<h2>Managing Errors</h2> - -<p>If you have error reporting enabled in your <dfn>config/database.php</dfn> file you'll see a standard error message if the commit was unsuccessful. If debugging is turned off, you can -manage your own errors like this:</p> - -<code> -$this->db->trans_start();<br /> -$this->db->query('AN SQL QUERY...');<br /> -$this->db->query('ANOTHER QUERY...');<br /> -$this->db->trans_complete();<br /> -<br /> -if (<kbd>$this->db->trans_status()</kbd> === FALSE)<br /> -{<br /> - // generate an error... or use the log_message() function to log your error<br /> -} -</code> - - -<h2>Enabling Transactions</h2> - -<p>Transactions are enabled automatically the moment you use <dfn>$this->db->trans_start()</dfn>. If you would like to disable transactions you -can do so using <dfn>$this->db->trans_off()</dfn>:</p> - -<code> -<kbd>$this->db->trans_off()</kbd><br /><br /> - -$this->db->trans_start();<br /> -$this->db->query('AN SQL QUERY...');<br /> -$this->db->trans_complete(); -</code> - -<p class="important">When transactions are disabled, your queries will be auto-commited, just as they are when running queries without transactions.</p> - - -<h2>Test Mode</h2> - -<p>You can optionally put the transaction system into "test mode", which will cause your queries to be rolled back -- even if the queries produce a valid result. -To use test mode simply set the first parameter in the <dfn>$this->db->trans_start()</dfn> function to <samp>TRUE</samp>:</p> - -<code> -$this->db->trans_start(<samp>TRUE</samp>); // Query will be rolled back<br /> -$this->db->query('AN SQL QUERY...');<br /> -$this->db->trans_complete(); -</code> - - -<h2>Running Transactions Manually</h2> - -<p>If you would like to run transactions manually you can do so as follows:</p> - -<code> -$this->db->trans_begin();<br /><br /> - -$this->db->query('AN SQL QUERY...');<br /> -$this->db->query('ANOTHER QUERY...');<br /> -$this->db->query('AND YET ANOTHER QUERY...');<br /> - -<br /> - -if ($this->db->trans_status() === FALSE)<br /> -{<br /> - $this->db->trans_rollback();<br /> -}<br /> -else<br /> -{<br /> - $this->db->trans_commit();<br /> -}<br /> -</code> - -<p class="important"><strong>Note:</strong> Make sure to use <kbd>$this->db->trans_begin()</kbd> when running manual transactions, <strong>NOT</strong> -<dfn>$this->db->trans_start()</dfn>.</p> - - - - -</div> -<!-- END CONTENT --> - - -<div id="footer"> -<p> -Previous Topic: <a href="fields.html">Field MetaData</a> · -<a href="#top">Top of Page</a> · -<a href="../index.html">User Guide Home</a> · -Next Topic: <a href="table_data.html">Table Metadata</a> -</p> -<p><a href="http://codeigniter.com">CodeIgniter</a> · Copyright © 2006 - 2011 · <a href="http://ellislab.com/">EllisLab, Inc.</a></p> -</div> - -</body> -</html>
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