Selecting max value from calculated column in mysql

I have a mysql select statement which goes like this开发者_C百科:

Select a,b,calculated_column from table t1;

I come up with the calculated_column based on some logic and calculated_column is NOT a column in table t1.

How do I make this select statement return only the max value of the calculated_column?

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Try using a derived table:

SELECT MAX(calculated_column) AS MyMax
FROM 
(
    SELECT a,b,calculated_column 
    FROM   table t1;
) t2