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Database Utilities Class
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<h1>Database Utilities Class</h1>

<p>The Database Utilities Class contains functions that help you manage your database.</p>

<p class="important"><strong>Important:</strong>&nbsp; This class must be initialized independently since it is a separate class from the main Database class. 
More info below...</p>


<h2>Initializing the Utilities Class</h2>

<p>To initialize this class please use the following code:</p>

<code>$this->load->dbutil()</code>

<p>You can also autoload this class from within your <dfn>config/autoload.php</dfn> file by specifying <kbd>dbutil</kbd> in the <samp>$autoload['libraries']</samp> array.</p>

<p>Once initialized you will access the functions using the <dfn>$this->dbutil</dfn> object:</p>

<code>$this->dbutil->some_function()</code>



<h2>$this->dbutil->create_database('db_name')</h2>

<p>Permits you to create a database using the name specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p>

<code>if ($this->dbutil->create_database('my_db'))<br />
{<br />
&nbsp;&nbsp;&nbsp; echo 'Database created!';<br />
}</code>


<h2>$this->dbutil->drop_database('table_name')</h2>

<p>Permits you to drop a database using the table name specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p>

<code>if ($this->dbutil->drop_database('my_db'))<br />
{<br />
&nbsp;&nbsp;&nbsp; echo 'Database deleted!';<br />
}</code>


<h2>$this->dbutil->list_databases()</h2>

<p>Returns an array of database names:</p>


<code>
$dbs = $this->dbutil->list_databases();<br />
<br />
foreach($dbs as $db)<br />
{<br />
&nbsp;&nbsp;&nbsp; echo $db;<br />
}</code>



<h2>$this->dbutil->list_tables();</h2>

<p>Returns an array containing the names of all the tables in the database you are currently connected to.  Example:</p>

<code>$tables = $this->dbutil->list_tables()<br />
<br />
foreach ($tables as $table)<br />
{<br />
&nbsp;&nbsp;&nbsp; echo $table;<br />
}
</code>


<h2>$this->dbutil->table_exists();</h2>

<p>Sometimes it's helpful to know whether a particular table exists before running an operation on it.
Returns a boolean TRUE/FALSE.  Usage example:</p>

<code>
if ($this->dbutil->table_exists('table_name'))<br />
{<br />
&nbsp;&nbsp;&nbsp; // some code...<br />
}
</code>

<p>Note:  Replace <em>table_name</em> with the name of the table you are looking for.</p>


<h2>$this->dbutil->optimize_table('table_name');</h2>

<p>Permits you to optimize a table using the table name specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p>

<code>
if ($this->dbutil->optimize_table('table_name'))<br />
{<br />
&nbsp;&nbsp;&nbsp; echo 'Success!'<br />
}
</code>

<p><strong>Note:</strong> Not all database platforms support table optimization.</p>


<h2>$this->dbutil->repair_table('table_name');</h2>

<p>Permits you to repair a table using the table name specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p>

<code>
if ($this->dbutil->optimize_table('table_name'))<br />
{<br />
&nbsp;&nbsp;&nbsp; echo 'Success!'<br />
}
</code>

<p><strong>Note:</strong> Not all database platforms support table repairs.</p>



<h2>$this->dbutil->optimize_database();</h2>

<p>Permits you to optimize the database your DB class is currently connected to. Returns an array containing the returned status messages or FALSE on failure.</p>

<code>
$result = $this->dbutil->optimize_databas();<br />
<br />
if ($result !== FALSE)<br />
{<br />
&nbsp;&nbsp;&nbsp; print_r($result);<br />
}
</code>

<p><strong>Note:</strong> Not all database platforms support table optimization.</p>



<h2>$this->dbutil->cvs_from_result($db_result)</h2>

<p>Permits you to generate a CVS file from a query result. The first parameter of the function must contain the result object from your query. 
Example:</p>

<code>
$this->load->dbutil();<br />
<br />
$query = $this->db->query("SELECT * FROM mytable");<br />
<br />
echo $this->dbutil->cvs_from_result($query);
</code>

<p>The second and third parameters allows you to 
set the delimiter and newline character.  By default tabs are used as the delimiter and "\n" is used as a new line.  Example:

<code>
$delimiter = ",";<br />
$newline = "\r\n";<br />
<br />
echo $this->dbutil->cvs_from_result($query, $delimiter, $newline);
</code>

<p class="important"><strong>Important:</strong>&nbsp; This function will NOT write the CVS file for you.  It simply creates the CVS layout.
If you need to write the file use the <a href="../helpers/file_helper.html">File Helper</a>.</p>



<h2>$this->dbutil->xml_from_result($db_result)</h2>

<p>Permits you to generate an XML file from a query result. The first parameter expects a query result object, the second 
may contain an optional array of config parameters.  Example:</p>

<code>
$this->load->dbutil();<br />
<br />
$query = $this->db->query("SELECT * FROM mytable");<br />
<br />
$config = array (<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'root'&nbsp;&nbsp;&nbsp; => 'root',<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'element' => 'element', <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'newline' => "\n", <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;';tab'&nbsp;&nbsp;&nbsp;&nbsp;=> "\t"<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;);<br />
<br />
echo $this->dbutil->cvs_from_result($query, $config);
</code>

<p class="important"><strong>Important:</strong>&nbsp; This function will NOT write the CVS file for you.  It simply creates the CVS layout.
If you need to write the file use the <a href="../helpers/file_helper.html">File Helper</a>.</p>






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