GROUP BY or COUNT Like Field Values - UNPIVOT?

Question

I have a table with test fields, Example

id         | test1    | test2    | test3    | test4    | test5
+----------+----------+----------+----------+----------+-         


        

Answer 1

You could use an auxiliary on-the-fly table to turn columns into rows, then you would be able to apply aggregate functions, something like this:

SELECT
  SUM(fields = 'P') AS passed,
  SUM(fields = 'F') AS failed,
  SUM(fields = 'I') AS incomplete
FROM (
  SELECT
    t.id,
    CASE x.idx
      WHEN 1 THEN t.test1
      WHEN 2 THEN t.test2
      WHEN 3 THEN t.test3
      WHEN 4 THEN t.test4
      WHEN 5 THEN t.test5
    END AS fields
  FROM atable t
    CROSS JOIN (
      SELECT 1 AS idx
      UNION ALL SELECT 2
      UNION ALL SELECT 3
      UNION ALL SELECT 4
      UNION ALL SELECT 5
    ) x
  WHERE t.id = 12345
) s