public function get( $row_key, $columns = '*' ) {
		return $this->get_by( $this->table->get_primary_key(), $row_key, $columns );
	}
public function get( $row_key, $columns = '*' ) {
		return $this->get_by( $this->table->get_primary_key(), $row_key, $columns );
	}
public function get ( $ row_key , $ columns = '*' ) { return $ this -> get_by ( $ this -> table -> get_primary_key ( ) , $ row_key , $ columns ) ; }
Retrieve a row by the primary key

@since 1.0

@param string       $row_key
@param array|string $columns

@return object

@throws Exception
Retrieve a row by the primary key