For every unique constraint on a column, SQL server will create which of the following?

For every unique constraint on a column, SQL server will create which of the following?

• An entry for that column
• A non-clustered index for that column
• A clustered index for that column
• A filtered index 

 

EXPLANATION

For every unique constraint on a column, SQL server creates a non-clustered index. A non-clustered index has a structure separate from the data rows. It contains non-clustered index key values and each key value entry has a pointer to the data row that contains the key value.