[SOLVED] Derived Column to handled mulitple conditions in CASE statement?

Derived Column to handled mulitple conditions in CASE statement?

I've got a CASE statement that works, but because I have to do it in SSIS, I am at a loss:

SELECT [BPCNUM_0], TYPE,

CASE

    WHEN [TYPE]=1 THEN 'Normal'
    WHEN [TYPE]=2 THEN 'Divers'
    WHEN [TYPE]=3 THEN 'Intra-Société'
    WHEN [TYPE]=4 THEN 'Prospect'
END AS TYPE
FROM table

As you can see, the case statement evaluates values in one column and renames them depending on what they are. when I tried this with SSIS, it didn't work

[TYPE] == 1 ? "Normal" : [TYPE] == 2 ? "Divers" : [TYPE] == 3 ? "Intra-Société" : [TYPE] == 4 ? "Prospect"

I tried also

[TYPE] == "1" ? "Normal" : [TYPE] == "2" ? "Divers" : [TYPE] == "3" ? "Intra-Société" : [TYPE] == "4" ? "Prospect"

but also it didn't work.

Solution

Your expression needs to add a final ELSE statement since it should know the value to assign in case non of the previous conditions is validated:

[TYPE] == 1 ? "Normal" : 
[TYPE] == 2 ? "Divers" : 
[TYPE] == 3 ? "Intra-Société" : 
[TYPE] == 4 ? "Prospect" : ""

Which is equivalent to the following in SQL:

SELECT [BPCNUM_0], TYPE,

CASE

    WHEN [TYPE]=1 THEN 'Normal'
    WHEN [TYPE]=2 THEN 'Divers'
    WHEN [TYPE]=3 THEN 'Intra-Société'
    WHEN [TYPE]=4 THEN 'Prospect'
    ELSE ''
END AS TYPE
FROM table

If you need to assign a NULL value instead of an empty string, you can use the following expression (Assuming that the derived column type is DT_WSTR):

[TYPE] == 1 ? "Normal" : 
[TYPE] == 2 ? "Divers" : 
[TYPE] == 3 ? "Intra-Société" : 
[TYPE] == 4 ? "Prospect" : NULL(DT_WSTR,50)