The following SELECT statement:
SELECT lname, serviceyrs, DENSE_RANK()OVER(ORDER BY serviceyrs) FROM schooltbl GROUP BY 1,2;
returns the ordered ranking by service years for teachers listed in schooltbl.
| lname | serviceyrs | DENSE_RANK |
|---|---|---|
| Adams | 10 | 1 |
| Peters | 10 | 1 |
| Murray | 10 | 1 |
| Rogers | 15 | 2 |
| Franklin | 16 | 3 |
| Smith | 20 | 4 |
| Ford | 20 | 4 |
| Derby | 20 | 4 |
| Baker | 25 | 5 |