Does the order of columns in a columnstore index matter?

Question

I have a table with ~200 million rows and ~15 columns in it. I am planning to create a COLUMNSTORE index on my table.

Will there be any change in performance based on the order of columns that I use in the columnstore index? If yes, what is the logic behind it?

Answer 1

No, order does not matter. Each column is considered individually.

From the SQL Server team (emphasis added):

Typically you will want to put all the columns in your table into the columnstore index. It does not matter what order you list the columns because a columnstore index does not have a key like a B-tree index does. Internally, the data will be re-ordered automatically to get the best compression.

Answer 2

order doesn't matter, what does matter if that you should include ALL columns from the base table in the columnstore index - more via my previous answer to this question here

Answer 3

In SQL Server 2012-2016 you have the concept of Segment elimination (http://social.technet.microsoft.com/wiki/contents/articles/5651.understanding-segment-elimination.aspx) and you actually can force the order of at least 1 column (plus 1 extra inside each of the partition).

Consider the following article that explains data loading for better segment elimination: Data Loading for Better Segment Elimination

Answer 4

There is an existing great answer by Aaron from 2012, To expand on that...

With SQL 2014+ you have clustered columnstore indexes available. When creating a clustered columnstore index there are no column selection or order options available. Columnstore Indexes Described