Is there a simpler way to find MODE(S) of some values in MySQL

Question

MODE is the value that occurs the MOST times in the data, there can be ONE MODE or MANY MODES

here\'s some values in two tables (sqlFiddle)

create ta         


        

Answer 1

You are very close with the last query. The following finds one mode:

SELECT value, occurs
FROM (SELECT value,count(*) as occurs
      FROM t200
      GROUP BY `value`
      LIMIT 1
     ) T1

I think your question was about multiple modes, though:

SELECT value, occurs
FROM (SELECT value, count(*) as occurs
      FROM t200
      GROUP BY `value`
     ) T1
WHERE occurs = (select max(occurs)
                from (select `value`, count(*) as occurs
                      from t200
                      group by `value`
                     ) t
               );

EDIT:

This is much easier in almost any other database. MySQL supports neither with nor window/analytic functions.

Your query (shown below) does not do what you think it is doing:

  SELECT value, occurs  
  FROM (SELECT value, count(*) as occurs
        FROM t200
        GROUP BY `value`
       ) T1
  HAVING occurs = max(occurs) ; 

The final having clause refers to the variable occurs but does use max(occurs). Because of the use of max(occurs) this is an aggregation query that returns one row, summarizing all rows from the subquery.

The variable occurs is not using for grouping. So, what value does MySQL use? It uses an arbitrary value from one of the rows in the subquery. This arbitrary value might match, or it might not. But, the value only comes from one row. There is no iteration over it.