I'm trying to replace the Null Value of my excel file into 0, but got an error "Data type DT_14 and DT_WSTR are incompatible for binary operator "==". I'm using a derived column and so far here's my expression 20150921 == "" ? 0 : 20150928 I have also tried this one, ISNULL(20150921) ? 0 : 20150921 but the data being passed to the destination is 20150921 instead of its real value.
By the way, 20150921 is string [DT_STR] type.
Also, there's a scenario where my column 20150928 changes into F11, F12 and So on. Why is that?
Newbie here! Sorry.
You are comparing number (20150921) with the string (""), that's why you got the error Data type DT_14 and DT_WSTR are incompatible for binary operator "==". Nevertheless your expression is almost correct, you just need to compare the name of column, instead of value of the column.
Example:
You have an excel file with column "Column1" which contains numbers (20150921) and some empty values. SSIS treats every Excel column as a string, so you have to convert it by the expression: Column1 == "" ? 0 : (DT_I4)Column1. That means every empty value will be transformed to 0, otherwise it will be just cast to integer (four bytes integer). You can also use data type DT_I8.
EDIT: In case your column is named 20150921, try to use [20150921] instead.