How to select the rows that have the same values in some columns?

data in table 'TEST':

column01, column02, column03
AAA, AAA,AAA
ABC,ABC,ABC
ACB, ACB, ACB
BAC, AAA, BAC



You can see that values of the column 'column02' are the same for the first row and the fourth row. They are both 'AAA'.


I would like to find out which value is duplicated in a certain column by executing a SQL select query. is this possible?

Thanks.

You culd do something like,

select A.* from myTable A, myTable B
where A.col1 = B.col1 or A.col2 = B.col2 or A.col3 = B.col3

Note: I haven't tested how good it performs

I should have made my question more clear. Actually what I wanted to do is a query like


select a.column02 from TEST a, TEST b where a.column02 != b.column02 and a.column03 = a.column03



i just realized that it is not that complicated as i thought since the value of column03 is has to be distinct, but thanks anyway.