在MySQL中,若要在基本表student中增加一列class_name(课程名),可用以下哪个选项()。
A.ADDTABLEstudentALTER(class_nameVARCHAR(8))
B.ALTERTABLEstudentADD(class_nameVARCHAR(8))
C.ADDTABLES(class_nameVARCHAR(8))
D.ALTERTABLEstudet(ADDclass_nameVARCHAR(8))
A.ADDTABLEstudentALTER(class_nameVARCHAR(8))
B.ALTERTABLEstudentADD(class_nameVARCHAR(8))
C.ADDTABLES(class_nameVARCHAR(8))
D.ALTERTABLEstudet(ADDclass_nameVARCHAR(8))
A.ALTER TABLE S (ADD CNAME CHAR(8))
B.ADD TABLE S ALTER (CNAME CHAR(8))
C.ALTER TABLE S ADD (CNAME CHAR(8))
D.ADD TABLE S (CNAME CHAR(8))
A.性别字段为空
B.学号重复
C.参照完整性约束
D.以上都不是
day(出生日期、varchar型),score(成绩、int型)。现要向学员表中插入一名学员的信息,下列SQL语句正确的是()。
A、INSERT INTO students VALUES(1,'李刚’,’1999-01-01', 80)
B、INSERT INT0 students(sID,sName,birthday)VALUES(1,’李刚’,’1999-01-01',80)
C、INSERT INTO students VALUES (1,李刚,1999-01-01,80)
D、 INSERT INT0 students(sID, sName, birthday)VALUES(NULL,’李刚’,‘1999-01-01')
A.UPDATE TABLE food RENAME TO fruit
B.UPDATE TABLE fruit RENAME TO food
C.ALTER TABLE fruit RENAME TO food
D.ALTER TABLE food RENAME TO fruit