CodeIgniter MySQL "on duplicate key update"

mysql_addon

source: http://web.archive.org/web/20090221091226/http://codeigniter.com/forums/viewthread/80958/

add function to two files
1st file: /system/database/drivers/mysql/mysql_driver.php and perhaps file mysqli_driver.php too

	/**
	* ON DUPLICATE UPDATE statement
	*
	* Generates a platform-specific on duplicate key update string from the supplied data
	*
	* @author    Chris Miller <chrismill03@hotmail.com>
	* @since     1.6.2
	* @access    public
	* @param     string   the table name
	* @param     array    the update/insert data
	* @return    string
	*/

	function _escape_table($table)
	{
		return $table;
	}	

	function _duplicate_insert($table, $values)
	{
	    $updatestr = array();
	    $keystr    = array();
	    $valstr    = array();
	    
	    foreach($values as $key => $val)
	    {
	        $updatestr[] = $key." = ".$val;
	        $keystr[]    = $key;
	        $valstr[]    = $val;
	    }
	    
	    $sql  = "INSERT INTO ".$this->_escape_table($table)." (".implode(', ',$keystr).") ";
	    $sql .= "VALUES (".implode(', ',$valstr).") ";
	    $sql .= "ON DUPLICATE KEY UPDATE ".implode(', ',$updatestr);

	    return $sql;
	}
	
2nd file: /system/database/DB_active_rec.php

	/**
	* On Duplicate Key Update
	*
	* Compiles an on duplicate key update string and runs the query
	*
	* @author    Chris Miller <chrismill03@hotmail.com>
	* @since     1.6.2
	* @access    public
	* @param     string    the table to retrieve the results from
	* @param     array     an associative array of update value
	* @return    object
	*/

	function on_duplicate($table = '', $set = NULL )
	{
	    if ( ! is_null($set))
	    {
	        $this->set($set);
	    }

	    if (count($this->ar_set) == 0)
	    {
	            if ($this->db_debug)
	        {
	                return $this->display_error('db_must_use_set');
	        }
	            return FALSE;
	    }

	    if ($table == '')
	    {
	        if ( ! isset($this->ar_from[0]))
	        {
	            if ($this->db_debug)
	            {
	                return $this->display_error('db_must_set_table');
	            }
	            return FALSE;
	        }
	        
	        $table = $this->ar_from[0];
	    }
	    
	        
	    $sql = $this->_duplicate_insert($this->_protect_identifiers($this->dbprefix.$table), $this->ar_set );
	        
	    $this->_reset_write();
	    return $this->query($sql);
	} 


how to use:

	$data = array(
	  'id'    => 10,
	  'title' => 'title',
	  'name'  => 'name',
	  'date'  => 'date'
	);
	
	$this->db->on_duplicate('mytable', $data);