| <!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> | |
| <title>CodeIgniter User Guide : Generating Query Results</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="Content-Type" content="text/html; charset=utf-8" /> | |
| <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.jpg" width="153" height="44" 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 1.6.0</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 script | |
| execution. 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 been | |
| generated 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 © 2007 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p> | |
| </div> | |
| </body> | |
| </html> |