Question

I used another table and generated a MySQL views, by using that view I coded the below:

SELECT staffid,
   CASE Frequency
     WHEN 'Less' THEN COUNT(Frequency)
     ELSE '0'
  END AS LessCount,
  CASE Frequency
     WHEN 'Full' THEN COUNT(Frequency)
     ELSE '0'
  END AS FullCount,
  CASE Frequency
     WHEN 'More' THEN COUNT(Frequency)
     ELSE '0'
  END AS MoreCount
FROM effort_frequency
GROUP BY staffid, Frequency

I used the above code to get the below table:

+-------+-----------+-----------+-----------+
| staff | lessCount | FullCount | MoreCount |
+-------+-----------+-----------+-----------+
|   10  |    2      |    0      |    0      |
|   10  |    0      |    1      |    0      |
|   10  |    0      |    0      |    3      |
|   11  |    1      |    0      |    0      |
|   11  |    0      |    3      |    0      |
+-------+-----------+-----------+-----------+

I need this to be converted, which should look like:

+-------+-----------+-----------+-----------+
| staff | lessCount | FullCount | MoreCount |
+-------+-----------+-----------+-----------+
|   10  |    2      |    1      |    3      |
|   11  |    1      |    3      |    0      |
+-------+-----------+-----------+-----------+

How we can do this in MySQL ?

Answer 1

SELECT   staffid               AS staff,
         SUM(Frequency='Less') AS lessCount,
         SUM(Frequency='Full') AS FullCount,
         SUM(Frequency='More') AS MoreCount
FROM     effort_frequency
GROUP BY staffid