Get rows matching all items from an array

Question

I can do it with a loop or an alternate solution, but this would mean time consuming (on page loading).... So I would like to know if there is a 'one query' solution.

I have a table containing 4 columns:

id   class    day    hour
 1   9b3      1      3      
 2   9b4      1      3
 3   9b5      1      3
 4   9b3      1      5
 5   9b4      2      6
 6   9b5      2      6
 7   9b4      4      7
 8   9b3      3      6
 9   9b4      3      6
 10  9b5      3      6

What I need is to recover the day and hour matching all three classes 9b3, 9b4, 9b5 at the same day and hour.

In the example above, the result should be:

day   hour
1      3
3      6

Answer 1

Try this:

SELECT day,hour
FROM yourTableName
WHERE class IN ('9b3','9b4','9b5')
GROUP BY day,hour
HAVING COUNT(class) = 3;

sqlfiddle demo

Answer 2

also that works...

SELECT day,hour
FROM Table1
WHERE (class = '9b3' or class =  '9b4' or class = '9b5')
GROUP BY day,hour
HAVING COUNT(class) = 3;