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| <td><h1>Code Igniter User Guide Version 1.5.0b3</h1></td> | |
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| Queries | |
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| <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>$this->db->query()</dfn> function. It ONLY returns TRUE/FALSE on success or failure. | |
| It DOES NOT return a database result set, nor does it set the query timer, or compile bind data, or store your query for debugging. | |
| It simply lets you submit a query. Most users will rarely use this function.</p> | |
| <h1>Escaping Queries</h1> | |
| <p>It's a very good security practice to escape your data before submitting it into your database. | |
| Code Igniter has two functions that help you do this:</p> | |
| <ol> | |
| </li> | |
| <li><strong>$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>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> | |
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