I need an SSIS expression to get the left part of a string before the separator, and then put the new string in a new column. I checked in derived column, it seems no such expressions. Substring could only return string part with fixed length.
For example, with separator string - :
Art-Reading Should return Art
Art-Writing Should return Art
Science-chemistry Should return Science
P.S.
I knew this could be done in MySQL with SUBSTRING_INDEX(), but I'm looking for an equivalent in SSIS, or at least in SQL Server

