How can you create an alias for a table in a SQL query?

In SQL, you can create an alias for a table in a query to give the table a temporary, alternative name that you can use in the query. Table aliases are particularly useful when you need to reference the same table multiple times in a query, or when you want to make your query more readable.

 Here's how to create a table alias in a SQL query:

Basic Syntax:

SELECT alias.column_name

FROM table_name AS alias;

• alias: This is the temporary name you want to assign to the table. You can choose any name you prefer.
• column_name: The specific columns you want to retrieve from the table.
• table_name: The name of the table you want to alias.
• AS: The keyword used to define the alias. It is optional in some SQL dialects.

Example:

Suppose you have a table named "employees," and you want to create an alias "e" for it in your query. You can then reference the columns of the "employees" table using this alias:

SELECT e.employee_id, e.first_name, e.last_name

FROM employees AS e

WHERE e.department = 'Sales';

In this example:

We've assigned the alias "e" to the "employees" table using the AS keyword.

The alias "e" is then used to specify the columns we want to retrieve and in the WHERE clause for filtering.

Table aliases not only make your SQL queries more readable but also become necessary when you are dealing with self-joins (joining a table to itself) or when you need to reference the same table multiple times in a complex query.