1. | Use sub query as a virtual table | | |
2. | Compare with data from subquery | | |
3. | An example of a nested three-level subquery | | |
4. | If an inner query returns a NULL, the outer query also returns NULL | | |
5. | Working with multi-column subqueries | | |
6. | Use aggregate function in sub query | | |
7. | Sub query: 'SELECT 1 FROM dept d' | | |
8. | Using the EXISTS and NOT EXISTS operators | | |
9. | Writing Single Row Subqueries | | |
10. | Compare with the sub query result | | |
11. | Subqueries in a HAVING Clause: Uses a subquery in the HAVING clause of the outer query | | |
12. | Subqueries in a FROM Clause (Inline Views) | | |
13. | Single Row Subqueries May Return a Maximum of One Row | | |
14. | Subqueries May Not Contain an ORDER BY Clause | | |
15. | Sub query with table join | | |
16. | Writing Multiple Column Subqueries with table join | | |
17. | Subquery just returns a literal value: improve performance of your query | | |
18. | EXISTS typically offers better performance than IN with subqueries | | |
19. | NVL() is used to convert null in correlated query | | |
20. | Writing Nested Subqueries | | |
21. | subqueries in the SELECT column list (New Way) | | |
22. | subqueries in the SELECT column list (Old way) | | |
23. | Not equals and subquery | | |
24. | Greater than average salary | | |
25. | Greater than max(salary) | | |
26. | Larger than value from subquery | | |
27. | Subquery in select statement | | |
28. | Subquery in where clause | | |
29. | Subqueries That Return Multiple Results | | |
30. | Subqueries in the WHERE Clause: equals | | |
31. | Subqueries in the WHERE Clause: less than | | |
32. | Simple Subqueries in select statement | | |
33. | Single-row subqueries return only one row of result. | | |
34. | The parent query of a single-row subquery can return more than one row. | | |
35. | Born after employee 4 was born | | |
36. | inline view: What percentage of these items exist in each bin selected | | |