A: select name from teacher where email=null
B: select name from teacher where email<>null
C: select name from teacher where email is null
D: select name from teacher where email is not null
举一反三
- 下面哪一个语句,显示没有Email地址的教师姓名() A: Select name from teacher where email=NULL; B: Select name from teacher where email C: Select name from teacher where email is NULL; D: Select name from teacher where emailis not NULL;
- 查询student表中的所有非空email信息, 以下语句正确的是（ ） A: Select email from student where email !=null B: Select email from student where email not is null C: Select email from student where email <> null D: Select email from student where email is not null
- 若想查询student表中name为空值的记录，则正确的SQL语句是（ ）。 A: SELECT * FROM student WHERE name = NULL; B: SELECT * FROM student WHERE name like NULL; C: SELECT * FROM student WHERE name = 'NULL'; D: SELECT * FROM student WHERE name is NULL;
- 若想查询student表中name为空值的记录，则正确的SQL语句是（1.0分） A: select * from student where name = null; B: select * from student where name link null; C: select * from student where name = 'null'; D: select * from student where name is null;
- 若在教师表中查找还没有输入工龄的记录,使用的SQL语句为 A: SELECT * FROM 教师 WHERE 工龄IS NOT NULL B: SELECT * FROM 教师 WHERE 工龄=0 C: SELECT * FROM 教师 WHERE 工龄 IS NULL D: SELECT * FROM 教师 WHERE 工龄=NULL
内容
- 0
在Oracle中，有一个教师表teacher的结构如下： ID NUMBER(5) NAME VARCHAR2(25) EMAIL VARCHAR2(50) 下面哪个语句显示没有Email地址的教师姓名；
- 1
若在教师表中查找还没有输入工龄的记录，使用的SQL语句为 A: A) SELECT * FROM 教师 WHERE 工龄 IS NOT NULL B: B) SELECT * FROM 教师 WHERE 工龄＝0 C: C) SELECT * FROM 教师 WHERE 工龄 IS NULL D: D) SELECT * FROM 教师 WHERE 工龄＝NULL
- 2
在student表中显示所有姓马的学生的姓名、生日和Email。下列语句可以实现的（ ） A: select sname,birthdate,email from student where sname like ‘马%’ B: select sname,birthdate,email from student where sname rike ‘马.*’; C: select sname,birthdate,email from student where sname like ‘%马‘ D: select sname,birthdate,email from student where sname =’*马*’
- 3
教师表teacher的“职称”字段可能的取值为:教授、副教授、讲师和助教 要查找职称为教授或副教授的教师,错误的语句是______。 A: SELECT * FROM teacher WHERE 职称 IN("教授", "副教授"); B: SELECT * FROM teacher WHERE RIGHT(职称, 2)="教授"; C: SELECT * FROM teacher WHERE 职称="教授" OR 职称="副教授"; D: SELECT * FROM teacher WHERE 职称="教授" AND 职称="副教授";
- 4
【单选题】查找:姓名不为空的记录,SELECT语句的条件子句正确的是()。 A. WHERE NAME !NULL B. WHERE NAME NOT NULL C. WHERE NAME IS NOT NULL D. WHERE NAME !=NULL