data warehouse - How do I replace "?" with NULL in SSIS expression?

Question

There are ? in my data columns and I have to replace them with NULL.

Answer 1

if a question mark is in the column already it must be some kind of string.

Use a derived column and a if function:

[colName] == "?" ? NULL(DT_STR, ?length?, 1252) : [colName]

or

[colName] == "?" ? NULL(DT_WSTR, ?length?) : [colName]