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<title>Database Quick Start : CodeIgniter User Guide</title>
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<td><h1>CodeIgniter User Guide Version 2.2.0</h1></td>
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<a href="http://codeigniter.com/">CodeIgniter Home</a> ›
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<a href="index.html">Database Library</a> ›
Database Example Code
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<h1>Database Quick Start: Example Code</h1>
<p>The following page contains example code showing how the database class is used. For complete details please
read the individual pages describing each function.</p>
<h2>Initializing the Database Class</h2>
<p>The following code loads and initializes the database class based on your <a href="configuration.html">configuration</a> settings:</p>
<code>$this->load->database();</code>
<p>Once loaded the class is ready to be used as described below.</p>
<p>Note: If all your pages require database access you can connect automatically. See the <a href="connecting.html">connecting</a> page for details.</p>
<h2>Standard Query With Multiple Results (Object Version)</h2>
<code>$query = $this->db->query('SELECT name, title, email FROM my_table');<br />
<br />
foreach ($query->result() as $row)<br />
{<br />
echo $row->title;<br />
echo $row->name;<br />
echo $row->email;<br />
}<br />
<br />
echo 'Total Results: ' . $query->num_rows();
</code>
<p>The above <dfn>result()</dfn> function returns an array of <strong>objects</strong>. Example: $row->title</p>
<h2>Standard Query With Multiple Results (Array Version)</h2>
<code>$query = $this->db->query('SELECT name, title, email FROM my_table');<br />
<br />
foreach ($query->result_array() as $row)<br />
{<br />
echo $row['title'];<br />
echo $row['name'];<br />
echo $row['email'];<br />
}</code>
<p>The above <dfn>result_array()</dfn> function returns an array of standard array indexes. Example: $row['title']</p>
<h2>Testing for Results</h2>
<p>If you run queries that might <strong>not</strong> produce a result, you are encouraged to test for a result first
using the <dfn>num_rows()</dfn> function:</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 $row->body;<br />
}<br />
}
</code>
<h2>Standard Query With Single Result</h2>
<code>$query = $this->db->query('SELECT name FROM my_table LIMIT 1');<br />
<br />
$row = $query->row();<br />
echo $row->name;<br />
</code>
<p>The above <dfn>row()</dfn> function returns an <strong>object</strong>. Example: $row->name</p>
<h2>Standard Query With Single Result (Array version)</h2>
<code>$query = $this->db->query('SELECT name FROM my_table LIMIT 1');<br />
<br />
$row = $query->row_array();<br />
echo $row['name'];<br />
</code>
<p>The above <dfn>row_array()</dfn> function returns an <strong>array</strong>. Example: $row['name']</p>
<h2>Standard Insert</h2>
<code>
$sql = "INSERT INTO mytable (title, name) <br />
VALUES (".$this->db->escape($title).", ".$this->db->escape($name).")";<br />
<br />
$this->db->query($sql);<br />
<br />
echo $this->db->affected_rows();
</code>
<h2>Active Record Query</h2>
<p>The <a href="active_record.html">Active Record Pattern</a> gives you a simplified means of retrieving data:</p>
<code>
$query = $this->db->get('table_name');<br />
<br />
foreach ($query->result() as $row)<br />
{<br />
echo $row->title;<br />
}</code>
<p>The above <dfn>get()</dfn> function retrieves all the results from the supplied table.
The <a href="active_record.html">Active Record</a> class contains a full compliment of functions
for working with data.</p>
<h2>Active Record Insert</h2>
<code>
$data = array(<br />
'title' => $title,<br />
'name' => $name,<br />
'date' => $date<br />
);<br />
<br />
$this->db->insert('mytable', $data);
<br /><br />
// Produces: INSERT INTO mytable (title, name, date) VALUES ('{$title}', '{$name}', '{$date}')</code>
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