Lesson 15
Intermediate Level
15 of 30 lessons
Aliases and Column Naming
Learn how to use column and table aliases for better query readability. Aliases make your SQL queries more readable and maintainable.
What Are Aliases?
An alias is a temporary name assigned to a column or table. Aliases make output more readable and are useful in expressions or when using joins.
Syntax
SELECT column_name AS alias_name
FROM table_name;
-- You can also use quotes for aliases with spaces
SELECT first_name AS "Employee Name"
FROM employees;
Table Alias Example
-- Alias table name
SELECT e.first_name, e.salary
FROM employees e;
Why Use Aliases?
- Make column names more readable in results
- Shorten table names in complex queries
- Use in expressions and calculated fields
Examples
-- Rename column in output
SELECT first_name AS "Name", salary AS "Monthly Salary"
FROM employees;
-- Alias in calculated column
SELECT salary * 12 AS "Annual Salary"
FROM employees;
Practice Task
- Display employee name and annual salary using an alias for both columns.