• 2022-06-16 问题

    以下语句表示_____连接。(填汉字)SELECT Reader.*,ReaderType.* FROM Reader INNER JOIN ReaderType ON Reader.TypeID=ReaderType.TypeID

    以下语句表示_____连接。(填汉字)SELECT Reader.*,ReaderType.* FROM Reader INNER JOIN ReaderType ON Reader.TypeID=ReaderType.TypeID

  • 2022-06-08 问题

    以下语句从__个表中进行查询。(填数字)SELECT Reader. *,ReaderType.* FROM Reader, ReaderType where Reader.TypeID=ReaderType.TypeID

    以下语句从__个表中进行查询。(填数字)SELECT Reader. *,ReaderType.* FROM Reader, ReaderType where Reader.TypeID=ReaderType.TypeID

  • 2022-06-16 问题

    删除ReaderType表中所有数据,正确的命令是 A: DELETE TABLE ReaderType B: DELETE ReaderType C: DROP TABLE ReaderType D: DROP ReaderType

    删除ReaderType表中所有数据,正确的命令是 A: DELETE TABLE ReaderType B: DELETE ReaderType C: DROP TABLE ReaderType D: DROP ReaderType

  • 2021-04-14 问题

    删除ReaderType表中“企业职工”的信息,正确的语句是

    删除ReaderType表中“企业职工”的信息,正确的语句是

  • 2022-06-16 问题

    智慧职教: 更新borrow表每条借书记录的eprdate(到期日期)。 borrow  eprdate=timestampadd(day,(select maxdays from readertype where typeID in (select typeID from reader where reader.readerID=.)),brwdate);

    智慧职教: 更新borrow表每条借书记录的eprdate(到期日期)。 borrow  eprdate=timestampadd(day,(select maxdays from readertype where typeID in (select typeID from reader where reader.readerID=.)),brwdate);

  • 2022-06-07 问题

    为表ReaderType的LimitNum字段添加检查约束,要求教该字段的值<3,正确的语句是 A: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum=3) B: ALTER TABLE ReaderTypeADD CONSTRAINT check (LimitNum<3) C: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum (LimitNum<3) D: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum<3)

    为表ReaderType的LimitNum字段添加检查约束,要求教该字段的值<3,正确的语句是 A: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum=3) B: ALTER TABLE ReaderTypeADD CONSTRAINT check (LimitNum<3) C: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum (LimitNum<3) D: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum<3)

  • 2022-06-07 问题

    为表ReaderType的LimitNum字段添加检查约束,要求教师类型中该字段的值+3,正确的语句是 A: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum=LimitNum+3) B: ALTER TABLE ReaderTypeADD CONSTRAINT check (LimitNum=LimitNum+3) WHERE Typename='教师' C: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum (LimitNum=LimitNum+3) WHERE Typename='教师' D: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum=LimitNum+3) WHERE Typename='教师'

    为表ReaderType的LimitNum字段添加检查约束,要求教师类型中该字段的值+3,正确的语句是 A: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum=LimitNum+3) B: ALTER TABLE ReaderTypeADD CONSTRAINT check (LimitNum=LimitNum+3) WHERE Typename='教师' C: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum (LimitNum=LimitNum+3) WHERE Typename='教师' D: ALTER TABLE ReaderTypeADD CONSTRAINT CK_ReaderType_LimitNum check (LimitNum=LimitNum+3) WHERE Typename='教师'

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