Aliases (AS)

AS renames a column (or table) in the output only — it doesn't touch the underlying schema.

Source data — Pattern 1: Basic Data Retrieval

All queries run against the shared employees table (see schema.sql).

Aliases (AS) — source table 1

What it does

AS renames a column (or table) in the output only — it doesn't touch the underlying schema. Useful for friendlier report headings, or for naming a computed expression so you can refer to it clearly.

Problem

Display employee names with the heading 'Employee Name'.

SELECT first_name AS "Employee Name"
FROM employees;

Aliases (AS) — result 1

Dialect note

MySQL/PostgreSQL accept double quotes or backticks for the alias; SQL Server uses square brackets ([Employee Name]).