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MySQL - Column name aliases

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Created by:

maxsior322

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In this article, we would like to show you how to use aliases in MySQL.

Quick solution:

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SELECT `column_name` AS `alias_name`
FROM `table_name`;

Aliases are used to give a table or a column in the table a temporary name to make it more readable. They only exist for the duration of a query.

We create aliases using AS keyword.

Practical example

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To show how aliases work, we will use the following table:

MySQL - example data used to present aliases

Note:

At the end of this article you can find database preparation SQL queries.

Example 1

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In this example, we will display the average salary.

Query:

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SELECT AVG(`salary`) AS `average_salary`
FROM `users`;

Output:

Example 2

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In this example, we will display the number of users.

Query:

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SELECT COUNT(*) AS `number_of_users`
FROM `users`;

Output:

Database preparation

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create_tables.sql file:

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CREATE TABLE `users` (
    `id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
    `name` VARCHAR(50) NOT NULL,
    `surname` VARCHAR(50) NOT NULL,
    `department_id` INT(10) UNSIGNED,
    `salary` DECIMAL(15,2) NOT NULL,
    PRIMARY KEY (`id`)
);

insert_data.sql file:

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INSERT INTO `users`
    ( `name`, `surname`, `department_id`, `salary`)
VALUES
    ('John', 'Stewart', 1, '3512.00'),
    ('Chris', 'Brown', 2, '1344.00'),
    ('Kate', 'Lewis', 3, '6574.00'),
    ('Ailisa', 'Gomez', NULL, '6500.00'),
    ('Gwendolyn', 'James', 2, '4200.00'),
    ('Simon', 'Collins', 4, '3320.00'),
    ('Taylor', 'Martin', 2, '1500.00'),
    ('Andrew', 'Thompson', NULL, '2100.00');