判斷題主鍵要求列中的值是唯一值。

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4.單項(xiàng)選擇題在SQL查詢語(yǔ)句中,"UPDATE Student SET補(bǔ)助=補(bǔ)助+1.2"的意思是()

A:將Student表中的所有記錄的補(bǔ)助均增加1.2
B:將Student表中的當(dāng)前記錄的補(bǔ)助增加1.2
C:將Student表中的所有記錄的補(bǔ)助均設(shè)置為1.2
D:將Student表中的當(dāng)前記錄的補(bǔ)助設(shè)置為1.2

5.單項(xiàng)選擇題根據(jù)關(guān)系模型Teacher(編號(hào),姓名),下列語(yǔ)句能完成插入一條新記錄的是()

A:INSERT INTO Teacher VALUES("070044","付強(qiáng)")
B:INSERT INTO Teacher(學(xué)號(hào),姓名)
C:INSERT("070044","付強(qiáng)")INTO Teacher
D:INSERT(學(xué)號(hào),姓名)INTO Teacher

6.單項(xiàng)選擇題將表Teacher中職稱字段為"助教"人員改為"講師",應(yīng)為()

A:UPDATE Teacher SET職稱="助教"WHERE職稱="講師"
B:UPDATE Teacher SET職稱="講師"WHERE職稱="助教"
C:UPDATE SET職稱="助教"WHERE職稱="講師"FROMTeacher
D:UPDATE SET職稱="講師"WHERE職稱="助教"FROMTeacher

7.單項(xiàng)選擇題刪除表Teacher中編號(hào)為070041的記錄,應(yīng)為()

A:DELETE FROM Teacher WHERE編號(hào)="070041"
B:DELETE FROM Teacher 編號(hào)="070041"
C:DELETE編號(hào)="070041"FROMTeacher
D:DELETE FROM Teacher WHERE編號(hào)IS"070041"

8.單項(xiàng)選擇題根據(jù)關(guān)系模型Teacher(編號(hào),職稱)下列SQL語(yǔ)句正確的是()

A:INSERT INTO Teacher(編號(hào),職稱)VALUES("070041","助教")
B:INSERT INTO Teacher("070041","助教")VALUES(編號(hào),職稱)
C:INSERT INTO VALUES(編號(hào),職稱)Teacher("070041","助教")
D:INSERT INTO VALUES("070041","助教")Teacher(編號(hào),職稱

10.單項(xiàng)選擇題假設(shè)某數(shù)據(jù)表中有一個(gè)"生日"字段,刪除80年出生的學(xué)生記錄的語(yǔ)句是()

A:DELETE FROM Student WHERE生日Between #80-01-01#And#80-12-31#
B:DELETE FROM Student WHERE生日Between("80-01-01"And"80-12-31")
C:DELETE FROM Student WHERE生日Between("80.01.01"And"80.12.31")
D:DELETE FROM Student WHERE生日Between #80.01.01#And#80.12.31#