SQL query for vice versa case

Question

I have similar table structure as shown below

Now here I want write a query (without using inner query) and find all those number who have condition like (value 1 = A and value 2 = B) and (value 1 = B and value 2 = A).

Means Kind of vice versa case where a number is having both value1 and value2 having A and B.

Thus for the given case my query output would be 1 and 4.

Answer 1

If you don't want to repeat the duplicate rows, following should work:

mysql> select a.* from tbl_so_q23676640 a
    ->  join tbl_so_q23676640 b
    ->  on a.v1 = b.v2 and a.v2 = b.v1
    -> where a.n=b.n
    -> group by a.n, a.v1, a.v2
    -> ;
+------+------+------+
| n    | v1   | v2   |
+------+------+------+
|    1 | a    | b    |
|    1 | b    | a    |
|    4 | a    | b    |
|    4 | b    | a    |
+------+------+------+
4 rows in set (0.00 sec)

Answer 2

Please try this query:

select t1.NUMBER from mytable t1
join mytable t2 on t1.NUMBER = t2.NUMBER
where t1.Value1 = 'A' and t1.Value2 = 'B' and t2.Value1 = 'B' and t2.Value2 = 'A'

You can check the result: http://sqlfiddle.com/#!2/a5e7ae/1

Answer 3

SELECT NUMBER FROM MYTABLE WHERE value1 = 'A' and value2 = 'B'
INTERSECT
SELECT NUMBER FROM MYTABLE WHERE value2 = 'A' and value1 = 'B';