删除STUDENT表中C2的默认值约束语句是()。
A: ALTER TABLE STUDENT DROP CONSTRAINT C2
B: DROP CONSTRAINT C2
C: DELETE CONSTRAINT C2
D: DROP STUDENT
A: ALTER TABLE STUDENT DROP CONSTRAINT C2
B: DROP CONSTRAINT C2
C: DELETE CONSTRAINT C2
D: DROP STUDENT
举一反三
- 以下哪条命令用于删除一个约束()。 A: Alter TABLE MODIFY CONSTRAINT B: Drop CONSTRAINT C: Alter TABLE Drop CONSTRAINT D: Alter CONSTRAINT Drop
- 如果要删除表中的约束,应该使用( ) A: ALTER TABLE 表名DROP CONSTRAINT 约束名 B: DROP CONSTRAINT 约束名 C: DELETE CONSTRAINT 约束名 D: ALTER TABLE 表名DELETE CONSTRAINT 约束名
- 删除约束用什么语句 A: delete B: delete constraint C: drop D: drop constraint
- 删除当前数据库中的表Student的语句应当是( )。 A: DELETE TABLE Student B: DELETE Student C: DROP Student D: DROP TABLE Student
- 用于删除数据表student正确的语句是: A: drop student B: delete student C: drop database student D: drop table student