若要使所有学科80分以上的成绩都增加5%, 80至60分的成绩都增加10%,应如何更新数据库( )。 A.UPDATE SC SET GRADE=GRADE*1.05 WHERE SC.GRADE>=80 UPDATE SC SET GRADE=GRADE* 1.10 WHERE SC.GRADE>=60 AND SC.GRADE <=80 B.UPDATE SC SET GRADE=GRADE* 1.10 WHERE SC.GRADE>=60 AND SC.GRADE<=80 UPDATE SC SET GRADE=GRADE* 1.05 WHERE SC.GRADE>=80 C.UPDATE SC SET GRADE=GRADE* 1.05 WIRE SC.GRADE>=80 AND SET GRADE =GRADE* 1.10 WHARE SC.GRADE>=60 D.UPDATE SC SET GRADE=GRADE* 1.10 WHERE SC.GRADE>=60 AND SC.GRADE <=80 AND SET GRADE=GRADE* 1.05 WHERE SC.GRADE>=80
- AUPDATE SC SET GRADE=GRADE*1.05 WHERE SC.GRADE>=80 UPDATE SC SET GRADE=GRADE* 1.10 WHERE SC.GRADE>=60 AND SC.GRADE <=80
- BUPDATE SC SET GRADE=GRADE* 1.10 WHERE S
- CGRADE>=60 AND SC.GRADE<=80 UPDATE SC SET GRADE=GRADE* 1.05 WHERE SC.GRADE>=80 C.UPDATE SC SET GRADE=GRADE* 1.05 WIRE SC.GRADE>=80 AND SET GRADE =GRADE* 1.10 WHARE SC.GRADE>=60
- DUPDATE SC SET GRADE=GRADE* 1.10 WHERE SC.GRADE>=60 AND SC.GRADE <=80 AND SET GRADE=GRADE* 1.05 WHERE SC.GRADE>=80