FULL JOIN is an SQL operator used to retrieve all records from both the left and right tables.
It returns matching records where available and NULL for unmatched records in either table. In this process, the columns act as operands.
Syntax:
SELECT columns FROM table1 LEFT JOIN table2 ON table1.common_column = table2.common_column UNION SELECT columns FROM table1 RIGHT JOIN table2 ON table1.common_column = table2.common_column
Example:
Table1: Employees Employee_id Name Department_id 1 Mohan 11 2 Anaya 12 3 Babita 13 Table2: Departments Department_id Department_name 11 HR 12 IT 14 Finance
SQL Query:
SELECT Employees.name, Departments.department_name FROM Employees LEFT JOIN Departments ON Employees.department_id = Departments.department_id UNION SELECT Employees.name, Departments.department_name FROM Employees RIGHT JOIN Departments ON Employees.department_id =Departments.department_id;
Output:
Name Department_name Mohan HR Anaya IT NULL Finance Babita NULL