How to get the max of two values in MySQL?

mysql max

I tried but failed:

mysql> select max(1,0);

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual 
that corresponds to your MySQL server version for the right syntax to use 
near '0)' at line 1

NinethSense

Use GREATEST()

E.g.:

SELECT GREATEST(2,1);

Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7)

one thing need to keep in mind that whenever if any single value contains null at that time this function always returns null as answer!

There is also LEAST

how can i run a sub query as a parameter to GREATEST so that i can get values for a cirtain column

To prevent the problem with null you can use ifnull. E.g. select greatest(date1, ifnull(date2, "0000-00-00 00.00:00")) from table1 where date2 is null; will get you date1.

If some values may be null, you can do GREATEST(COALESCE(column1, 0), COALESCE(column2, 0))

cs_alumnus

To get the maximum value of a column across a set of rows:

SELECT MAX(column1) FROM table; -- expect one result

To get the maximum value of a set of columns, literals, or variables for each row:

SELECT GREATEST(column1, 1, 0, @val) FROM table; -- expect many results

Watch out for null values with GREATEST. Any null value will cause the function to return null. To prevent this, you can do GREATEST(COALESCE(column1, 0), COALESCE(column2, 0))

Leonid Zakharov

You can use GREATEST function with not nullable fields. If one of this values (or both) can be NULL, don't use it (result can be NULL).

select 
    if(
        fieldA is NULL, 
        if(fieldB is NULL, NULL, fieldB), /* second NULL is default value */
        if(fieldB is NULL, field A, GREATEST(fieldA, fieldB))
    ) as maxValue

You can change NULL to your preferred default value (if both values is NULL).

This is why I honestly hate MySQL. What a tremendous amount of work to do such a simple thing.

This can be simply replaced with select COALESCE(GREATEST(fieldA, fieldB),fieldA,fieldB) as maxValue. It is overcomplicated

If some values can be null, you can do GREATEST(COALESCE(column1, 0), COALESCE(column2, 0))

How to get the max of two values in MySQL?

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