Ed Pollack continues a series on columnstore indexes:
This is worth a second mention: Avoid updates at all costs! Columnstore indexes do not treat updates efficiently. Sometimes they will perform well, especially against smaller tables, but against a large columnstore index, updates can be extremely expensive.
If data must be updated, structure it as a single delete operation followed by a single insert operation. This will take far less time to execute, cause less contention, and consume far fewer system resources.
Read on for several more tips along these lines.