diff options
Diffstat (limited to 'user_guide/database/queries.html')
-rw-r--r-- | user_guide/database/queries.html | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/user_guide/database/queries.html b/user_guide/database/queries.html new file mode 100644 index 000000000..e094486e1 --- /dev/null +++ b/user_guide/database/queries.html @@ -0,0 +1,142 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html>
+<head>
+
+<title>Code Igniter 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="../scripts/nav.js"></script>
+<script type="text/javascript" src="../scripts/prototype.lite.js"></script>
+<script type="text/javascript" src="../scripts/moo.fx.js"></script>
+<script type="text/javascript">
+window.onload = function() {
+ myHeight = new fx.Height('nav', {duration: 400});
+ myHeight.hide();
+}
+</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='Rick Ellis' />
+<meta name='description' content='Code Igniter 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>Code Igniter User Guide Version 1.4.1</h1></td>
+<td id="breadcrumb_right"><a href="../toc.html">Full Table of Contents</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://www.codeigniter.com/">Code Igniter Home</a> ›
+<a href="../index.html">User Guide Home</a> ›
+<a href="index.html">Database Library</a> ›
+Queries
+</td>
+<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="www.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>Queries</h1>
+
+<h2>$this->db->query();</h2>
+
+<p>To submit a query, use the following function:</p>
+
+<code>$this->db->query('YOUR QUERY HERE');</code>
+
+<p>The <dfn>query()</dfn> function returns a database result <strong>object</strong> when "read" type queries are run,
+which you can use to <a href="results.html">show your results</a>. When "write" type queries are run it simply returns TRUE or FALSE
+depending on success or failure. When retrieving data you will typically assign the query to your own variable, like this:</p>
+
+<code><var>$query</var> = $this->db->query('YOUR QUERY HERE');</code>
+
+<h2>$this->db->simple_query();</h2>
+
+<p>This is a simplified version of the <dfn>$this->db->query()</dfn> function. It ONLY returns TRUE/FALSE on success or failure.
+It DOES NOT return a database result set, nor does it set the query timer, or compile bind data, or store your query for debugging.
+It simply lets you submit a query. Most users will rarely use this function.</p>
+
+
+<h1><br />Escaping Queries</h1>
+
+<p>It's a very good security practice to escape your data before sumbiting it into your database.
+Code Igniter has two functions that help you do this:</p>
+
+<ol>
+</li>
+<li><strong>$this->db->escape()</strong> This function determines the data type so that it
+can escape only string data. It also automatically adds single quotes around the data so you don't have to:
+
+<code>$sql = "INSERT INTO table (title) VALUES(".$this->db->escape($title).")";</code>
+
+
+<li><strong>$this->db->escape_str()</strong> This function escapes the data passed to it, regardless of type.
+Most of the time you'll use the above function rather then this one. Use the function like this:
+
+<code>$sql = "INSERT INTO table (title) VALUES('".$this->db->escape_str($title)."')";</code>
+
+</li>
+</ol>
+
+
+<h1><br />Query Bindings</h1>
+
+
+<p>Bindings enable you to simplify your query syntax by letting the system put the queries together for you. Consider the following example:</p>
+
+<code>
+$sql = "SELECT * FROM some_table WHERE id = <var>?</var> AND status = <var>?</var> AND author = <var>?</var>";
+<br /><br />
+$this->db->query($sql, array(3, 'live', 'Rick'));
+</code>
+
+<p>The question marks in the query are automatically replaced with the values in the array in the second parameter of the query function.</p>
+<p class="important">The secondary benefit of using binds is that the values are automatically escaped, producing safer queries. You don't have to remember to manually escape data; the engine does it automatically for you.</p>
+
+
+
+</div>
+<!-- END CONTENT -->
+
+
+<div id="footer">
+<p>
+Previous Topic: <a href="connecting.html">Connecting to your Database</a>
+ ·
+<a href="#top">Top of Page</a> ·
+<a href="../index.html">User Guide Home</a> ·
+Next Topic: <a href="results.html">Query Results</a>
+<p>
+<p><a href="http://www.codeigniter.com">Code Igniter</a> · Copyright © 2006 · <a href="http://www.pmachine.com">pMachine, Inc.</a></p>
+</div>
+
+</body>
+</html>
\ No newline at end of file |