Question

I would like to understand how to set 0 value of the attribute when it is NULL with MAX function. For example:

Name columns:
number - date

Values:
10 - 2012-04-04
11 - 2012-04-04
12 - 2012-04-04
13 - 2012-04-15
14 - 2012-06-21
 1 - 2013-07-04

Number is incremental field, but it has set itself 1 when new year has come.
But result of:

SELECT (MAX(number)+1) number WHERE date LIKE "2014%" 

is NULL and not 1 because MAX(number) is NULL and not 0

Answer 1

Well, as there is no date like 2014, you would expect null, because the maximum of nothing is actually not anyting.

But do this:

COALESCE(MAX(number),0)

Which means: get the first non-null thing from the next list, so if your max is null, it’ll give you 0