-580 THE RESULT-EXPRESSIONS OF A CASE EXPRESSION CANNOT ALL BE NULL

result-expressions

Explanation
There is a CASE expression in the statement that has all the result-expressions (expressions following the THEN and ELSE keywords)
coded with the keyword NULL.

System action
The statement cannot be processed.

Programmer response
Change the CASE expression to include at least one result-expression with a keyword other than NULL.

SQLSTATE
42625 