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　更新可能なビューの定義はどれか。

　ア  CREATE  VIEW  VIEW1 (SNO, PNO)
          AS  SELECT  DISTINCT  SPJ.SNO, SPJ.PNO
              FROM  SPJ

　イ  CREATE  VIEW  VIEW2 (SNO, PNO)
          AS  SELECT  SPJ.SNO, SPJ.PNO
              FROM  SPJ
              GROUP　BY　SPJ.PNO

　ウ  CREATE  VIEW  VIEW3 (SNO, STATUS, CITY)
          AS  SELECT  S.SNO, S.STATUS, S.CITY
              FROM  S
              WHERE  S.STATUS > 15

　エ  CREATE  VIEW  VIEW4 (SCITY, PCITY)
          AS  SELECT  S.CITY, P.CITY
              FROM  S, SP, P
              WHERE  S.SNO = SP.SNO
              AND  SP.PNO = P.PNO

答えは○(ウ)
ア:× DISTINCTが入ってはいけない
イ:× GROUP BY句が入ってはいけない
ウ:○ 正解
エ:× FROM句は一つの表だけからなっていなければいけない