final public function isPrimaryKeyValue($value)
    {
        $column = $this->getPk();

        return (bool) $this->db->select($column)
                               ->from(static::getTableName())
                               ->whereEquals($column, $value)
                               ->query($column);
    }
final public function isPrimaryKeyValue($value)
    {
        $column = $this->getPk();

        return (bool) $this->db->select($column)
                               ->from(static::getTableName())
                               ->whereEquals($column, $value)
                               ->query($column);
    }
final public function isPrimaryKeyValue ( $ value ) { $ column = $ this -> getPk ( ) ; return ( bool ) $ this -> db -> select ( $ column ) -> from ( static :: getTableName ( ) ) -> whereEquals ( $ column , $ value ) -> query ( $ column ) ; }
Checks whether PK value exists

@param string $value PK's value
@return boolean
Checks whether PK value exists