Question

What is the purpose of the SQL AS clause?

(a) The AS SQL clause is used to change the name of a column in the result set or to assign a name to a derived column

(b) The AS clause is used with the JOIN clause only

(c) The AS clause defines a search condition

(d) All of the mentioned

I have been asked this question during an interview.

This intriguing question comes from Basic SQL in section Laying the Foundation of SQL Server

Answer 1

Correct answer is (a) The AS SQL clause is used to change the name of a column in the result set or to assign a name to a derived column

Easiest explanation: SQL Aliases are defined for columns and tables. Basically aliases are created to make the column selected more readable.