What is the benefit of Column Store Index over Row Store Index?

Answer:

Traditionally, indexes are stored in rowbased organization, also known as row store. This form of storage is extremely efficient when one row or a small range is requested. When a large range or all rows are returned, this organization can become inefficient.

The column store index favors the return of large ranges of rows by storing data in column-wise organization. When we create a column store index, we typically include all the columns in a table.
This ensures that all columns are included in the enhanced performance benefits of the column store organization. In data warehousing scenarios, often less than 15 percent of the columns in an index are needed for the
results of a query