几种比较运算符:
实例:
假设我们有下面的表:
sqlite> select * from student;
ID NAME AGE
----- ---------- ----------
1 xiaoming 18
2 xiaohua 18
3 mingming 19
4 xiaogang 20
那么,请看:
sqlite> select * from student where ID >2;
ID NAME AGE
----- ---------- ----------
3 mingming 19
4 xiaogang 20
sqlite> select * from student where AGE = 18;
ID NAME AGE
----- ---------- ----------
1 xiaoming 18
2 xiaohua 18
sqlite> select * from student where AGE != 18;
ID NAME AGE
----- ---------- ----------
3 mingming 19
4 xiaogang 20
请说明上面查询语句的意义?