Question

Hi I have select CASE statement in DB2:

case when actualfinish is not null then dec (( timestampdiff(
  4, 
  char(actualfinish - reportdate))/60.00),10,2)
else 'not'
 end

It returns me error.
If I delete ELSE part there is no error and calculation is done.

    case when actualfinish is not null then dec (( timestampdiff(
      4, 
      char(actualfinish - reportdate))/60.00),10,2)
end

If I change THEN part to something like

  case when actualfinish is not null then 'Yes'
    else 'not'
     end

also there is no error.

But for my complete SQL query – can’t find an error.
Thanks

Answer 1

Issue here is that dec function returns a decimal datatype in the else part of the CASE statement you are returning a VARCHAR, hence the issue.

In your second version
case when actualfinish is not null then 'Yes'
else 'not'
end

Both the when and else are returning same datatype hence the query runs fine.

Change your else to send a decimal equivalent value and it should execute fine.

Update:

Use this version if you can return decimal as a string:

CASE 
    WHEN actualfinish IS NOT NULL THEN CHAR(DEC((TIMESTAMPDIFF(4, CHAR(actualfinish - reportdate))/60.00),10,2))
    ELSE 'not'
END