/**
* This function creates a data reader for query the specified SQL statement.
*
* @access public
* @param string $sql the SQL statement
* @return DB_SQL_DataReader the SQL data reader
* @throws Throwable_SQL_Exception indicates that the query failed
*/
public function reader($sql)
{
if (!$this->is_connected()) {
throw new Throwable_SQL_Exception('Message: Failed to create SQL data reader. Reason: Unable to find connection.');
}
$reader = DB_SQL_DataReader::factory($this, $sql);
$this->sql = $sql;
return $reader;
}
/**
* This function processes an SQL statement that will return data.
*
* @access public
* @override
* @param string $sql the SQL statement
* @param string $type the return type to be used
* @return DB_ResultSet the result set
* @throws Throwable_SQL_Exception indicates that the query failed
*/
public function query($sql, $type = 'array')
{
if (!$this->is_connected()) {
throw new Throwable_SQL_Exception('Message: Failed to query SQL statement. Reason: Unable to find connection.');
}
$result_set = $this->cache($sql, $type);
if ($result_set !== NULL) {
$this->insert_id = FALSE;
$this->sql = $sql;
return $result_set;
}
$reader = DB_SQL_DataReader::factory($this, $sql);
$result_set = $this->cache($sql, $type, new DB_ResultSet($reader, $type));
$this->insert_id = FALSE;
$this->sql = $sql;
return $result_set;
}