TYPES OF JOIN USED IN MYSQL

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Definition: INNER JOIN

Returns rows where there is a match in both tables based on the common id.

SELECT * FROM employee INNER JOIN department ON employee.id = department.id;


Definition: LEFT JOIN

Returns all rows from the "employee" table and matched rows from the "department" table. If there is no match, NULL values are returned for "department" columns.

SELECT * FROM employee LEFT JOIN department ON employee.id = department.id;


Definition: RIGHT JOIN

Returns all rows from the "department" table and matched rows from the "employee" table. If there is no match, NULL values are returned for "employee" columns.

SELECT * FROM employee RIGHT JOIN department ON employee.id = department.id;


Definition: FULL JOIN

Returns all rows when there is a match in either "employee" or "department" table. If there is no match, NULL values are returned for columns from the table without a match.

SELECT * FROM employee FULL JOIN department ON employee.id = department.id;


Definition: CROSS JOIN

Returns all the records of "employee" and "department" tables, i.e., all possible combinations.

SELECT * FROM employee CROSS JOIN department;

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