Mysql max value from 3 different columns

Question

Is there any way to find maximum value of 3 different columns? I\'m trying to find records with any of 3 columns value higher than specified value and trying to avoid making

Answer 1

you need to use GREATEST

like that

    select id from tablex where GREATEST(column1, column2, column3) > 69

Answer 2

I want to point out that:

where GREATEST(column1, column2, column3) > 69;

is not the same as:

where column1 > 69 or column2 > 69 or column3 > 69;

The first will filter out all rows where any of the three columns is NULL. The second will still consider these rows. You could rewrite the GREATEST() query as:

where GREATEST(coalesce(column1, 0), coalesce(column2, 0), coalesce(column3, 0)) > 69;

but that defeats the purpose of the simpler syntax. You may know that the column values are never NULL, in which case using greatest() is ok. But, it is not a general substitute.