MySQL Group by - Get columns with zero count

Question

I tried decrying other answers, no luck, hence asking.

I have one table and few more similar to this for other year Here is the table structure

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Answer 1

The COUNT is only returning the COUNT for the status that he finds for Microsoft. And those are Denied and Wthdrawn. You have to feed the query all the statuses and COUNT the occurrences of all of them. The ones that don't appear will in the table will be left with 0:

SELECT a.STATUS, 
      SUM(CASE 
        WHEN b.STATUS IS NOT NULL
          THEN 1
        ELSE 0
      END) AS StatusCount
FROM (
  SELECT DISTINCT STATUS
  FROM tab1
  ) a
LEFT JOIN tab1 b ON a.STATUS = b.STATUS AND b.CompanyName = 'Microsoft'
GROUP BY a.STATUS;

What this does is:

SELECT DISTINCT STATUS
FROM tab1

This finds all the statuses possible. If you have a reference table with all the possible statuses, even better Use it instead of this query.

Then you do a LEFT JOIN on this table by status and companyName. This way, you will only get a match in STATUS if there is a record on the table. If there is, you add 1 to the SUM, otherwise you Add 0.

sqlfiddle demo

Answer 2

A fairly straight forward way is to get all distinct statuses and LEFT JOIN with the table to get the counts;

SELECT a.status, COUNT(b.status) cnt
FROM (SELECT DISTINCT status FROM Table1) a
LEFT JOIN Table1 b
  ON a.status = b.status
 AND b.`Company name`='Microsoft'
GROUP BY a.status

An SQLfiddle to test with.

Answer 3

You can nest a query, and search for when the Count is equal or greater than zero:

SELECT a.status, a.stat_count FROM (SELECT status, count(*) as stat_count FROM table where company like '%Google%' GROUP BY status) a WHERE a.stat_count >= 0