Quick Check

1.	Why should the size of the clustered index key be kept low?
2.	What is the maximum number of included columns allowed in a non-clustered index?
3.	What is the maximum number of columns that can make up an index key?

Answers

1.	Keep the clustered index small because it is copied into each row in each non-clustered index on the same table.
2.	1,023 columns is the maximum number of included columns allowed in a non-clustered index.
3.	16 columns (or a width of 900 bytes) is the maximum number of columns that can make up an index key.