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<!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>Generating Query Results : 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 1.7.1</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> › Query Results</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>Generating Query Results</h1><p>There are several ways to generate query results:</p><h2>result()</h2><p>This function returns the query result as an array of <strong>objects</strong>, or <strong>an empty array</strong> on failure.Typically you'll use this in a foreach loop, like this:</p><code>$query = $this->db->query("YOUR QUERY");<br /><br />foreach ($query->result() as $row)<br />{<br /> echo $row->title;<br /> echo $row->name;<br /> echo $row->body;<br />}</code><p>The above <dfn>function</dfn> is an alias of <dfn>result_object()</dfn>.</p><p>If you run queries that might <strong>not</strong> produce a result, you are encouraged to test the result first:</p><code>$query = $this->db->query("YOUR QUERY");<br /><br />if ($query->num_rows() > 0)<br />{<br /> foreach ($query->result() as $row)<br /> {<br /> echo $row->title;<br /> echo $row->name;<br /> echo $row->body;<br /> }<br />}</code><h2>result_array()</h2><p>This function returns the query result as a pure array, or an empty array when no result is produced. Typically you'll use this in a foreach loop, like this:</p><code>$query = $this->db->query("YOUR QUERY");<br /><br />foreach ($query->result_array() as $row)<br />{<br /> echo $row['title'];<br /> echo $row['name'];<br /> echo $row['body'];<br />}</code><h2>row()</h2><p>This function returns a single result row. If your query has more than one row, it returns only the first row.The result is returned as an <strong>object</strong>. Here's a usage example:</p><code>$query = $this->db->query("YOUR QUERY");<br /><br />if ($query->num_rows() > 0)<br />{<br /> $row = $query->row();<br /><br /> echo $row->title;<br /> echo $row->name;<br /> echo $row->body;<br />}</code><p>If you want a specific row returned you can submit the row number as a digit in the first parameter:</p><code>$row = $query->row(<dfn>5</dfn>);</code><h2>row_array()</h2><p>Identical to the above <var>row()</var> function, except it returns an array. Example:</p><code>$query = $this->db->query("YOUR QUERY");<br /><br />if ($query->num_rows() > 0)<br />{<br /> $row = $query->row_array();<br /><br /> echo $row['title'];<br /> echo $row['name'];<br /> echo $row['body'];<br />}</code><p>If you want a specific row returned you can submit the row number as a digit in the first parameter:</p><code>$row = $query->row_array(<dfn>5</dfn>);</code><p>In addition, you can walk forward/backwards/first/last through your results using these variations:</p><p><strong>$row = $query->first_row()</strong><br /><strong>$row = $query->last_row()</strong><br /><strong>$row = $query->next_row()</strong><br /><strong>$row = $query->previous_row()</strong></p><p>By default they return an object unless you put the word "array" in the parameter:</p><p><strong>$row = $query->first_row('array')</strong><br /><strong>$row = $query->last_row('array')</strong><br /><strong>$row = $query->next_row('array')</strong><br /><strong>$row = $query->previous_row('array')</strong></p><h1>Result Helper Functions</h1><h2>$query->num_rows()</h2><p>The number of rows returned by the query. Note: In this example, <dfn>$query</dfn> is the variable that the query result object is assigned to:</p><code>$query = $this->db->query('SELECT * FROM my_table');<br /><br />echo $query->num_rows();</code><h2>$query->num_fields()</h2><p>The number of FIELDS (columns) returned by the query. Make sure to call the function using your query result object:</p><code>$query = $this->db->query('SELECT * FROM my_table');<br /><br />echo $query->num_fields();</code><h2>$query->free_result()</h2><p>It frees the memory associated with the result and deletes the result resource ID. Normally PHP frees its memory automatically at the end of scriptexecution. However, if you are running a lot of queries in a particular script you might want to free the result after each query result has beengenerated in order to cut down on memory consumptions. Example:</p><code>$query = $this->db->query('SELECT title FROM my_table');<br /><br />foreach ($query->result() as $row)<br />{<br /> echo $row->title;<br />}<br />$query->free_result(); // The $query result object will no longer be available<br /><br />$query2 = $this->db->query('SELECT name FROM some_table');<br /><br />$row = $query2->row();<br />echo $row->name;<br />$query2->free_result(); // The $query2 result object will no longer be available</code></div><!-- END CONTENT --><div id="footer"><p>Previous Topic: <a href="queries.html">Queries</a> · <a href="#top">Top of Page</a> · <a href="../index.html">User Guide Home</a> · Next Topic: <a href="helpers.html">Query Helper Functions</a></p><p><a href="http://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p></div></body></html>