sql - AND query a m-to-n table -


i have simple m-to-n table in database , need perform , search. table looks follows:

column | column b 1          x 1          y 1          z 2          x 2          c 3          3          b 3          c 3          y 3          z 4          d 4          e 4          f 5          f 5          x 5          y

i want able 'give me column has x , y in column b (returning 1 , 5 here), can't figure out how form query.

i tried select column_a table column_b = x , columb_b = y seems return if column somehow both. fundamentally possible, or should have different table layout?

here's 1 way:

select table1 b in ('x', 'y') group having count(distinct(b)) = 2

sql fiddle

if guaranteed (a,b) unique, can rid of distinct well.


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