q:
in mysql, I want to add two fields. The SQL statement is as follows :
select c1 + c2 from table where Id = 1
now there is a problem, when the value of any field c1 or c2 is null, then the result of the addition is null, how to solve this problem?
a:
Select IFNULL(c1,0) + IFNULL(c2,0) from table where Id = 1
or use case when
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