在MYSQL数据库中查询某个字段不为空，下列哪个语法是正确的（）
A: SELECT*FROMworkWHEREinfoisnotNULL
B: SELECT*FROMworkWHEREinfo＝＝NULL；
C: SELECT*FROMworkWHEREinfo＝NULL；
D: SELECT*FROMworkWHEREinfoISNULL；
A: SELECT*FROMworkWHEREinfoisnotNULL
B: SELECT*FROMworkWHEREinfo＝＝NULL；
C: SELECT*FROMworkWHEREinfo＝NULL；
D: SELECT*FROMworkWHEREinfoISNULL；
举一反三
- 若查询考试成绩不为空的学生的学号，下列语句哪个是正确的？（ ） A: SELECT Sno FROM SC WHERE Grade >= 0； B: SELECT Sno FROM SC WHERE Grade ！= 0； C: SELECT Sno FROM SC WHERE Grade IS NOT NULL； D: SELECT Sno FROM SC WHERE Grade NOT IS NULL；
- 若查询考试成绩不为空的学生的学号,下列语句哪个是正确的? A: SELECT Sno FROM SC WHERE Grade >= 0； B: SELECT Sno FROM SC WHERE Grade！= 0； C: SELECT Sno FROM SC WHERE Grade NOT IS NULL； D: SELECT Sno FROM SC WHERE Grade 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;
- 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