Probs In Query

[sonia.sardana]

TABLE FIRST
Create table student1(roll int,marks int)
insert into student1 values(1,10)
insert into student1 values(2,20)
insert into student1 values(3,30)


TABLE SECOND
create table info(roll int,addr varchar(10))
insert into info values(1,'Delhi')
insert into info values(2,'Fbd')
insert into info values(4,'Gurgaon')


1)select info.roll from info ,student1 where info.roll=student1.roll
ANSWER IS RIGHT
1
2

2)select info.roll from info ,student1 where info.roll <> student1.roll
ANSWER is supposed to be Only Roll No 4.
But the result is coming out Different......

[ck9663]

TABLE FIRST
Create table student1(roll int,marks int)
insert into student1 values(1,10)
insert into student1 values(2,20)
insert into student1 values(3,30)


TABLE SECOND
create table info(roll int,addr varchar(10))
insert into info values(1,'Delhi')
insert into info values(2,'Fbd')
insert into info values(4,'Gurgaon')


1)select info.roll from info ,student1 where info.roll=student1.roll
ANSWER IS RIGHT
1
2

2)select info.roll from info ,student1 where info.roll <> student1.roll
ANSWER is supposed to be Only Roll No 4.
But the result is coming out Different......

Try WHERE NOT EXISTS or WHERE NOT IN

-- CK