A Base Model Template

class MY_Model extends Model
{
var $use_dbconfig = 'default';
var $id = null;
var $data = array();
var $table;
var $primary_key = 'id';
var $fields = array();
var $__insert_id = null;
var $__num_rows = null;
var $__affected_rows = null;
var $return_array = TRUE;
var $debug = FALSE;
var $queries = array();
var $_parent_name = '';

function MY_Model()
{
parent::Model();

$this->_assign_libraries( (method_exists($this, '__get') OR method_exists($this, '__set')) ? FALSE : TRUE );

// We don't want to assign the model object to itself when using the
// assign_libraries function below so we'll grab the name of the model parent
$this->_parent_name = ucfirst(get_class($this));

log_message('debug', "Model Class Initialized");
}

/**
* Assign Libraries
*
* Creates local references to all currently instantiated objects
* so that any syntax that can be legally used in a controller
* can be used within models.
*
* @access private
*/
function _assign_libraries($use_reference = TRUE)
{
$CI =& get_instance();
foreach (array_keys(get_object_vars($CI)) as $key)
{
if ( ! isset($this->$key) AND $key != $this->_parent_name)
{
// In some cases using references can cause
// problems so we'll conditionally use them
if ($use_reference == TRUE)
{
// Needed to prevent reference errors with some configurations
$this->$key = '';
$this->$key =& $CI->$key;
}
else
{
$this->$key = $CI->$key;
}
}
}
}

/**
* Load the associated database table.
*
* @author md emran hasan
* @access public
*/

function load_table($table, $config = 'default')
{
if ($this->debug) log_message('debug', "Loading model table: $table");

$this->table = $table;
$this->use_dbconfig = $config;

$this->load->database($config);
$this->fields = $this->db->list_fields($table);

if ($this->debug)
{
log_message('debug', "Successfull Loaded model table: $table");
}
}

/**
* Returns a resultset array with specified fields from database matching given conditions.
*
* @author md emran hasan
* @return query result either in array or in object based on model config
* @access public
*/

function find_all($conditions = NULL, $fields = '*', $order = NULL, $start = 0, $limit = NULL)
{
if ($conditions != NULL)
{
$this->db->where($conditions);
}

if ($fields != NULL)
{
$this->db->select($fields, FALSE);
}

if ($order != NULL)
{
$this->db->orderby($order);
}

if ($limit != NULL)
{
$this->db->limit($limit, $start);
}

$query = $this->db->get($this->table);
$this->__num_rows = $query->num_rows();

if ($this->debug)
{
$this->queries[] = $this->db->last_query();
}

return ($this->return_array) ? $query->result_array() : $query->result();
}

/**
* Return a single row as a resultset array with specified fields from database matching given conditions.
*
* @author md emran hasan
* @return single row either in array or in object based on model config
* @access public
*/

function find($conditions = NULL, $fields = '*', $order = 'id ASC')
{
$data = $this->find_all($conditions, $fields, $order, 0, 1);

if ($data)
{
return $data[0];
}
else
{
return false;
}
}

/**
* Returns contents of a field in a query matching given conditions.
*
* @author md emran hasan
* @return string the value of the field specified of the first row
* @access public
*/

function field($conditions = null, $name, $fields = '*', $order = 'id ASC')
{
$data = $this->find_all($conditions, $fields, $order, 0, 1);

if ($data)
{
$row = $data[0];

if (isset($row[$name]))
{
return $row[$name];
}
else
{
return false;
}
}
else
{
return false;
}

}

/**
* Returns number of rows matching given SQL condition.
*
* @author md emran hasan
* @return integer the number of records returned by the condition
* @access public
*/

function find_count($conditions = null)
{
$data = $this->find_all($conditions, 'COUNT(*) AS count', null, 0, 1);

if ($data)
{
return $data[0]['count'];
}
else
{
return false;
}
}



/**
* Returns a key value pair array from database matching given conditions.
*
* Example use: generateList(null, '', 0. 10, 'id', 'username');
* Returns: array('10' => 'emran', '11' => 'hasan')
*
* @author md emran hasan
* @return array a list of key val ue pairs given criteria
* @access public
*/

function generate_list($conditions = null, $order = 'id ASC', $start = 0, $limit = NULL, $key = null, $value = null, $first_key = '-1', $first_value = 'Inget valt')
{
$data = $this->find_all($conditions, "$key, $value", $order, $start, $limit);

if ($data)
{

if($first_key != NULL)
{
$keys[] = $first_key;
$vals[] = $first_value;
}

foreach ($data as $row)
{
$keys[] = ($this->return_array) ? $row[$key] : $row->$key;
$vals[] = ($this->return_array) ? $row[$value] : $row->$value;
}

if (!empty($keys) && !empty($vals))
{
$return = array_combine($keys, $vals);
return $return;
}
}
else
{
return false;
}
}

/**
* Returns an array of the values of a specific column from database matching given conditions.
*
* Example use: generateSingleArray(null, 'name');
*
* @author md emran hasan
* @return array a list of key value pairs given criteria
* @access public
*/

function generate_single_array($conditions = null, $field = null, $order = 'id ASC', $start = 0, $limit = NULL)
{
$data = $this->find_all($conditions, "$field", $order, $start, $limit);

if ($data)
{
foreach ($data as $row)
{
$arr[] = ($this->return_array) ? $row[$field] : $row->$field;
}

return $arr;
}
else
{
return false;
}
}

/**
* Initializes the model for writing a new record.
*
* @author md emran hasan
* @return boolean True
* @access public
*/

function create()
{
$this->id = false;
unset ($this->data);

$this->data = array();
return true;
}

/**
* Returns a list of fields from the database and saves in the model
*
* @author md emran hasan
* @return array Array of database fields
* @access public
*/

function read($id = null, $fields = null)
{
if ($id != null)
{
$this->id = $id;
}

$id = $this->id;

if ($this->id !== null && $this->id !== false)
{
$this->data = $this->find($this->primary_key . ' = ' . $id, $fields);
return $this->data;
}
else
{
return false;
}
}

/**
* Inserts a new record in the database.
*
* @author md emran hasan
* @return boolean success
* @access public
*/

function insert($data = null)
{
if ($data == null)
{
return FALSE;
}

$this->data = $data;
$this->data['create_date'] = date("Y-m-d H:i:s");

foreach ($this->data as $key => $value)
{
if (array_search($key, $this->fields) === FALSE)
{
unset($this->data[$key]);
}
}

$this->db->insert($this->table, $this->data);

if ($this->debug)
{
$this->queries[] = $this->db->last_query();
}

$this->__insert_id = $this->db->insert_id();
return $this->__insert_id;
}

/**
* Saves model data to the database.
*
* @author md emran hasan
* @return boolean success
* @access public
*/

function save($data = null, $id = null, $xss = TRUE)
{
if ($data)
{
$this->data = $data;
}

foreach ($this->data as $key => $value)
{

if (array_search($key, $this->fields) === FALSE)
{
unset($this->data[$key]);
}
}

if($xss)
{
$this->data = $this->input->xss_clean($this->data);
}

if ($id != null)
{
$this->id = $id;
}

$id = $this->id;

if ($this->id !== null && $this->id !== false)
{
$this->db->where($this->primary_key, $id);
$this->db->update($this->table, $this->data);

if ($this->debug)
{
$this->queries[] = $this->db->last_query();
}

$this->__affected_rows = $this->db->affected_rows();
return $this->id;
}
else
{
$this->db->insert($this->table, $this->data);

if ($this->debug)
{
$this->queries[] = $this->db->last_query();
}

$this->__insert_id = $this->db->insert_id();
return $this->__insert_id;
}
}



/**
* Removes record for given id. If no id is given, the current id is used. Returns true on success.
*
* @author md emran hasan
* @return boolean True on success
* @access public
*/

function remove($id = null)
{
if ($id != null)
{
$this->id = $id;
}

$id = $this->id;

if ($this->id !== null && $this->id !== false)
{
if ($this->db->delete($this->table, array($this->primary_key => $id)))
{
$this->id = null;
$this->data = array();

if ($this->debug)
{
$this->queries[] = $this->db->last_query();
}

return true;
}
else
{
return false;
}
}
else
{
return false;
}
}

/**
* Returns a resultset for given SQL statement. Generic SQL queries should be made with this method.
*
* @author md emran hasan
* @return array Resultset
* @access public
*/

function query($sql)
{
$ret = $this->db->query($sql);

if ($this->debug)
{
$this->queries[] = $this->db->last_query();
}

return $ret;
}

/**
* Returns the last query that was run (the query string, not the result).
*
* @author md emran hasan
* @return string SQL statement
* @access public
*/

function last_query()
{
return $this->db->last_query();
}

/**
* Returns the list of all queries peformed (if debug is TRUE)
*
* @author md emran hasan
* @return array list of SQL statements
* @access public
*/

function debug_queries()
{
$queries = array_reverse($this->queries);
return $queries;
}

/**
* This function simplifies the process of writing database inserts. It returns a correctly formatted SQL insert string.
*
* @author md emran hasan
* @return string SQL statement
* @access public
*/

function insert_string($data)
{
return $this->db->insert_string($this->table, $data);
}

/**
* Returns the current record's ID.
*
* @author md emran hasan
* @return integer The ID of the current record
* @access public
*/

function get_id()
{
return $this->id;
}

/**
* Returns the ID of the last record this Model inserted.
*
* @author md emran hasan
* @return int
* @access public
*/

function get_insert_id()
{
return $this->__insert_id;
}

/**
* Returns the number of rows returned from the last query.
*
* @author md emran hasan
* @return int
* @access public
*/

function get_num_rows()
{
return $this->__num_rows;
}

/**
* Returns the number of rows affected by the last query
*
* @author md emran hasan
* @return int
* @access public
*/

function get_affected_rows()
{
return $this->__affected_rows;
}
}