| Oracle PL / SQL » Select Query » GROUP BY |
| 1. | Using the GROUP BY Clause | ||
| 2. | Must include a nonaggregate column in the SELECT list in the GROUP BY clause | ||
| 3. | Use group by and avg | ||
| 4. | GROUP BY may be used on a column without the column name appearing in the result set | ||
| 5. | Grouping at Multiple Levels: group by more than one column | ||
| 6. | Column sequence in the group by impacts the ordering | ||
| 7. | Using the ORDER BY Clause to Sort Groups | ||
| 8. | You don't have to include the columns used in the GROUP BY clause in your SELECT clause | ||
| 9. | GROUP BY and HAVING clauses | ||
| 10. | Using a Column Multiple Times in a GROUP BY Clause |