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Diffstat (limited to 'user_guide/database/queries.html')
| -rw-r--r-- | user_guide/database/queries.html | 290 |
1 files changed, 145 insertions, 145 deletions
diff --git a/user_guide/database/queries.html b/user_guide/database/queries.html index 35f2da786..84c5f7f16 100644 --- a/user_guide/database/queries.html +++ b/user_guide/database/queries.html @@ -1,146 +1,146 @@ -<!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>
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-<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-<title>Queries : CodeIgniter User Guide</title>
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-<style type='text/css' media='all'>@import url('../userguide.css');</style>
-<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' />
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-<meta name='author' content='ExpressionEngine Dev Team' />
-<meta name='description' content='CodeIgniter User Guide' />
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-<div id="masthead">
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td><h1>CodeIgniter User Guide Version 1.7</h1></td>
-<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td>
-</tr>
-</table>
-</div>
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-<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> ›
-Queries
-</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>
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-</table>
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-
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-<br clear="all" />
-
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-<!-- 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>$this->db->query()</dfn> function. It ONLY returns TRUE/FALSE on success or failure.
-It DOES NOT return a database result set, nor does it set the query timer, or compile bind data, or store your query for debugging.
-It simply lets you submit a query. Most users will rarely use this function.</p>
-
-
-<h1>Adding Database prefixes manually</h1>
-<p>If you have configured a database prefix and would like to add it in manually for, you can use the following.</p>
-<p><code>$this->db->dbprefix('tablename');<br />
-// outputs prefix_tablename</code></p>
-
-
-<h1>Protecting identifiers</h1>
-<p>In many databases it is advisable to protect table and field names - for example with backticks in MySQL. <strong>Active Record queries are automatically protected</strong>, however if you need to manually protect an identifier you can use:</p>
-<p><code>$this->db->protect_identifiers('table_name');</code></p>
-
-<p>This function will also add a table prefix to your table, assuming you have a prefix specified in your database config file. To enable the prefixing set <kbd>TRUE</kbd> (boolen) via the second parameter:</p>
-<p><code>$this->db->protect_identifiers('table_name', <kbd>TRUE</kbd>);</code></p>
-
-
-<h1>Escaping Queries</h1>
-<p>It's a very good security practice to escape your data before submitting it into your database.
-CodeIgniter has two functions that help you do this:</p>
-
-<ol>
-<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>
-
-<li><strong>$this->db->escape_str()</strong> This function escapes the data passed to it, regardless of type.
-Most of the time you'll use the above function rather than this one. Use the function like this:
-
-<code>$sql = "INSERT INTO table (title) VALUES('".$this->db->escape_str($title)."')";</code></li>
-</ol>
-
-
-<h1>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://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p>
-</div>
-
-</body>
+<!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>Queries : 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</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> › +Queries +</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>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>$this->db->query()</dfn> function. It ONLY returns TRUE/FALSE on success or failure. +It DOES NOT return a database result set, nor does it set the query timer, or compile bind data, or store your query for debugging. +It simply lets you submit a query. Most users will rarely use this function.</p> + + +<h1>Adding Database prefixes manually</h1> +<p>If you have configured a database prefix and would like to add it in manually for, you can use the following.</p> +<p><code>$this->db->dbprefix('tablename');<br /> +// outputs prefix_tablename</code></p> + + +<h1>Protecting identifiers</h1> +<p>In many databases it is advisable to protect table and field names - for example with backticks in MySQL. <strong>Active Record queries are automatically protected</strong>, however if you need to manually protect an identifier you can use:</p> +<p><code>$this->db->protect_identifiers('table_name');</code></p> + +<p>This function will also add a table prefix to your table, assuming you have a prefix specified in your database config file. To enable the prefixing set <kbd>TRUE</kbd> (boolen) via the second parameter:</p> +<p><code>$this->db->protect_identifiers('table_name', <kbd>TRUE</kbd>);</code></p> + + +<h1>Escaping Queries</h1> +<p>It's a very good security practice to escape your data before submitting it into your database. +CodeIgniter has two functions that help you do this:</p> + +<ol> +<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> + +<li><strong>$this->db->escape_str()</strong> This function escapes the data passed to it, regardless of type. +Most of the time you'll use the above function rather than this one. Use the function like this: + +<code>$sql = "INSERT INTO table (title) VALUES('".$this->db->escape_str($title)."')";</code></li> +</ol> + + +<h1>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://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p> +</div> + +</body> </html>
\ No newline at end of file |