COUNT CASE And WHEN Statement In MySQL


Answer :

Use:



SELECT SUM(CASE 
             WHEN t.your_column IS NULL THEN 1
             ELSE 0
           END) AS numNull,
       SUM(CASE 
             WHEN t.your_column IS NOT NULL THEN 1
             ELSE 0
           END) AS numNotNull
  FROM YOUR_TABLE t


That will sum up the column NULL & not NULL for the entire table. It's likely you need a GROUP BY clause, depending on needs.



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