EN
MySQL - Select query
0
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In this article, we would like to show you how to make SELECT
query in MySQL.
Quick solution:
SELECT `column1`, `column2`, ...
FROM `table_name`;
SELECT * FROM `table_name`;
Practical example
To show how the SELECT
statement works, we will use the following table:
![MySQL - example data used with AVG() function](https://dirask.com/static/bucket/1617738354447-Jk7ANpVY90--image.png)
Note:
At the end of this article you can find database preparation SQL queries.
Example 1
In this example, we will display all names.
Query:
SELECT `name` AS `names` FROM `users`;
Output:
![MySQL - SELECT statement result (HeidiSQL)](/static/bucket/1617825860561-r6pQmGZDb5--image.png)
Example 2
In this example, we will display all the information about users.
Query:
SELECT * FROM `users`;
Output:
![MySQL - SELECT statement result (HeidiSQL)](/static/bucket/1617825993941-pmbQL7mAJX--image.png)
Database preparation
create_tables.sql
file:
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:
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');