Columnstore index proper usage

Question

I just learned about the wonders of columnstore indexes and how you can "Use the columnstore index to achieve up to 10x query performance gains over traditional row-oriented storage, and up to 7x data compression over the uncompressed data size."

With such sizable performance gains, is there really any reason to NOT use them?

Answer 1

The main disadvantage is that you'll have a hard time reading only a part of the index if the query contains a selective predicate. There are ways to do it (partitioning, segment elimination) but those are neither particularly easy to reliably implement nor do they scale to complex requirements.

For scan-only workloads columnstore indexes are pretty much ideal.