A: DELETE Age FROM S
B: ALTER TABLE DROP Age
C: UPDATE S Age
D: ALTER TABLE S ‘Age’
举一反三
- 学生表s有4个字段分别为:sno,sname,sex,age,要在表s中删除字段age,可选用的SQL语句是( )。 A: delete age from s; B: alter table s delete age; C: update s age; D: alter table s drop age;
- 姓名、性别、年龄。要在表S中删除一个属性“年龄”,可选用的SQL语句是()。 A: UPDATE S Age B: DELETE Age from S C: ALTER TABLE S ‘Age’ D: ALTER TABLE S DROP Age
- 若有关系St (NO,NAME,SEX,AGE),删除其中AGE字段的SQL语句是 ( )。 A: ALTER TABLE St DROP AGE B: DROP AGE FROM St C: ALTER TABLE St DELETE AGE D: DELETE AGE FROM St
- 设已有关系Student(Sno, Sname, Sex, Age),若欲删除该表中的属性Age,恰当的SQL语句是( )。 A: DELETE Age from Student B: UPDATE Student Age C: ALTER TABLE Student(Age) D: ALTER TABLE Student DROP Age
- 加入需要给stu表删除一个字段age,下列哪个正确 A: alter table stu drop age; B: drop table age C: drop table drop age;
内容
- 0
使用SQL语句将学生表S中年龄(AGE)大于30岁的记录删除,正确的命令是() A: DELETE FOR AGE>30 B: DELETE FROM S WHERE AGE>30 C: DELETE S FOR AGE>30 D: DELETE S WHERE AGE>30
- 1
用下面的语句创建了Student表:CREATE TABLE Student(Sno CHAR(10) primary key,Sname VARCHAR(10),age SMALLINT,Cname VARCHAR(20) );请用ALTER TABLE语句设置age字段默认值为20,正确的语句是()。 A: ALTER TABLE Student ALTER COLUMN age SET DEFAULT 20; B: ALTER TABLE Student CHANGE COLUMN age SET DEFAULT 20; C: ALTER TABLE Student ADD COLUMN age SET DEFAULT 20; D: ALTER TABLE Student DROP COLUMN age SET DEFAULT 20;
- 2
控制台修改表USER,往表中增加一个整形非空字段AGE的语句正确的是( )。 A: ALTER TABLE USER ADD AGE INT NOT NULL B: DROP TABLE USER C: CREATE TABLE IF NOT EXISTS USER D: ALTER TABLE USER AGE INT NOT NULL
- 3
下面选项中,用于将表user中字段age值更新为55的SQL语句是 A: ALTER TABLE user set age=55; B: UPDATE user set age=55 where age=55; C: UPDATE user set age=55; D: UPDATE user set age=55 where age<=55;
- 4
假设有三个基本表:学生表S、课程表C、学生选课表SC,它们的结构如下: S(S#,SN,SEX,AGE,DEPT) C(C#,CN) SC(S#,C#,GRADE)检索所有比“王华”年龄大的学生姓名、年龄和性别。正确的SQL语句是( )。 A: SELECT SN,AGE,SEX FROM S WHERE AGE>(SELECT AGE FROM S WHERE SN=”王华”) B: SELECT SN,AGE,SEX FROM S WHERE SN=”王华” C: SELECT SN,AGE,SEX FROM S WHERE AGE>(SELECT AGE WHERE SN=”王华”) D: SELECT SN,AGE,SEX FROM S WHERE AGE>王华.AGE