◦ 数値?日時?文字列? • 複数の結合条件 ◦ AND/OR/NOT • これらの条件をどうDBに保存する? どうオブジェクト指向として表現する? 演算子の例 equal (=) greater than (>) less than (<) greater than or equal to (>=) less than or equal to (<=) not equal to (!=) between is multiple is not multiple in the past of days in the past of months in between the past of days in between the past of manth