ROWNUM

Oracle

Example

SELECT ROWNUM, EMPLOYEE_ID, FIRST_NAME, LAST_NAME
FROM EMPLOYEES
WHERE ROWNUM <= 5;

Output

| ROWNUM | EMPLOYEE_ID | FIRST_NAME | LAST_NAME |
|--------|-------------|------------|-----------|
| 1      | 234         | John       | Doe       |
| 2      | 235         | Jane       | Smith     |
| 3      | 236         | Peter      | Parker    |
| 4      | 237         | Tony       | Stark     |
| 5      | 238         | Bruce      | Wayne     |

Explanation

In the SQL example given, the ROWNUM pseudocolumn is used in conjunction with the WHERE clause to limit the output to the first 5 rows retrieved from the EMPLOYEES table. The column sequence for the output is ROWNUM, EMPLOYEE_ID, FIRST_NAME, LAST_NAME.