SQL UNION ALL

Write SQL to UNION ALL of two or more statements.

The UNION ALL operator is used to combine the result-set of two or more SELECT statements and the result contains duplicate values.

Example

Table: Employee                            
+----+-------+--------+--------------+     
| Id | Name  | Salary | DepartmentId |     
+----+-------+--------+--------------+     
| 1  | Ram   | 85000  | 1            |     
| 2  | Henry | 80000  | 2            |     
| 3  | Sam   | 60000  | 2            |    
| 4  | Shyam | 60000  | 1            |
| 5  | Geeta | 90000  | 1            |
| 6  | Sheet | 90000  | 1            |
| 7  | Leela | 80000  | 1            |
| 8  | Geeta | 70000  | 1            |
+----+-------+--------+--------------+

Approach

Mysql

SELECT * FROM EMPLOYEE WHERE ID =1
UNION ALL
SELECT * FROM EMPLOYEE WHERE ID IN (1,2)

Oracle

SELECT * FROM EMPLOYEE WHERE ID =1
UNION ALL
SELECT * FROM EMPLOYEE WHERE ID IN (1,2)

Result

Table: Employee                            
+----+-------+--------+--------------+     
| Id | Name  | Salary | DepartmentId |     
+----+-------+--------+--------------+     
| 1  | Ram   | 85000  | 1            |     
| 1  | Ram   | 85000  | 1            |     
| 2  | Henry | 80000  | 2            |     
+----+-------+--------+--------------+