EXPRESSION SYNTAX REQUIRED FOR DERIVED COLUMN

Question

Hi
I've had a look around and can't find the correct syntax for an Expression in a Derived Column task.
Below is the logic in TSQL. Please could someone help me convert it?
CASE
WHEN FIELD1
=
'A'
AND FIELD2
IS
NULL
THEN
'A'
WHEN FIELD1
=
'B'
AND FIELD2
IS
NULL
THEN
'B'
WHEN FIELD1
=
'A'
AND FIELD2
=
'C'
THEN
'C_A'
WHEN FIELD1
=
'B'
AND FIELD2
=
'C'
THEN
'C_B'
WHEN FIELD1
=
'A'
AND FIELD2
=
'D'
THEN
'D_A'
WHEN FIELD1
=
'B'
AND FIELD2
=
'D'
THEN
'D_B'
ELSE
'0'
END
Thanks in advance
Lucy

Answer 1

Hi Lucy,
Try like below expression in derived columns.. 
 ((FIELD1 = 'A'
&& FIELD2 IS NULL)
? "A" :
  (FIELD1 = 'B'
&& FIELD2 IS NULL)
? "Y" :
(FIELD1 = 'A' && FIELD2 = 'C' )?
”C_A” :
(FIELD1 = 'B' && FIELD2 = 'C' )
? “'C_B” :
(FIELD1 = 'A' && FIELD2 = 'D' )
? “'D_A'” :
(FIELD1 = 'B' AND FIELD2 = 'D' )
? “'D_B”
: "0"))