Select email from student where email!=null
Select email from student where emailnotisnull
Select email from student where email<>null
Select email from student where emailisnotnull
第1题:
设有学生数据库:student(sno,sname,sex,age,dept)。现要查询所有刘姓学生的信息,可使用如下的 SQL语句:SELECT*FROM student WHERE【 】。
第2题:
从通信录表中查询姓名为张三的nickname字段和email字段的语句【 】。
第3题:
A、SELECT*FROMtbl_studentORDERBYstu_idASC;
B、SELECT*FROMtbl_studentORDERBYstu_idDESC;
C、SELECT*FROMtbl_studentstu_idORDERBYASC;
D、SELECT*FROMtbl_studentstu_idORDERBYDESC;
第4题:
对于学生信息表:student(sno,sname,sex,age,dept),要查询所有刘姓学生的信息,正确的语句是
A.SELECT * FROM student WHERE sname LIKE'刘 * '
B.SELECT * FROM student WHERE sname LIKE'刘 $'
C.SELECT * FROM student WHERE sname LIKE'刘%'
D.SELECT * FROM student WHERE sname LIKE'刘&'
第5题:
从员工信息表中查询姓名为张红的name字段和email字段的语句是【 】。
第6题:
根据SQL标准,要查询表student中所有年龄age小于所有学生的平均年龄的记录,下面哪条语句适用?()
A select * from student where age< avg(age)
B select * from student having age< avg(age)
C select * from student a where a.age< (select avg(b.age) from student b)
D select * from student a where (select avg(b.age) from student b ) >= a.age
第7题:
对于数据表:student(sno,sname,sex,age,grade),查询学习成绩为空的学生的学号和姓名,下面语句正确的是______。
A.SELECT sno,sname FROM student WHERE gade=NULL
B.SELECT sno,sname FROM student WHERE grade IS NULL
C.SELECT sno,age FROM student WHERE grade IS NULL
D.SELECT mo,age FROM student WHERE grade=NULL
第8题:
使用SQL语句从表STUDENT中查询所有姓王的同学的信息,正确的命令是:A)SELECT*FROM STUDENT WHERE LEFT(姓名,2)=“王”B)SELECT*FROM STUDENT WHERE RIGHT(姓名,2)=“王”C)SELECT*FROM STUDENT WHERE TRIM(姓名,2)=“王”D)SELECT*FROM STUDENT WHERE STR(姓名,2)=“王”
第9题:
使用SQL语句从表STUDENT中查询所有姓王的同学的信息,正确的命令是:______。
A.SELECT*FROM STUDENT WHERE LEFT(姓名,2)=“王”
B.SELECT*FROM STUDENT WHERE RIGHT(姓名,2)=“王”
C.SELECT*FROM STUDENT WHERE TRIM(姓名,2)=“王”
D.SELECT*FROM STUDENT WHERE STR(姓名,2)=“王”
第10题:
对于学生信息表:student(sno,sname,sex,age,grade),查询学习成绩为空的学生的学号和姓名,下面语句正确的是
A.SELECT sno,sname FROM student WHERE grade=NULL
B.SELECT sno,sname FROM student WHERE grade IS NULL
C.SELECT sno,age FROM student WHERE grade IS NULL
D.SELECT sno,age FROM student WHERE grade=NULL