- Published on
SQL
- Authors
- Name
- Lucian Oprea
- @LucianDSA_
00:30:00
Basics of SQL
⏷ 1. What are primary keys and foreign keys?
⏷ 2. Explain the difference between DDL, DML, DCL, and TCL.
⏷ 3. What are constraints in SQL?
Data Retrieval
⏷ 4. What is the difference between SELECT and SELECT DISTINCT?
⏷ 5. Why is it not recommended to use SELECT DISTINCT?
⏷ 6. What is the purpose of GROUP BY and HAVING?
⏷ 7. What is the difference between LIMIT and OFFSET?
Joins and Relationships
⏷ 8. What are the different types of joins in SQL?
⏷ 9. Explain the difference between INNER JOIN and OUTER JOIN.
⏷ 10. What is a self-join, and how is it used?
⏷ 11. What are cross joins and natural joins?
⏷ 12. How do you use multiple joins in a query?
Subqueries and Nested Queries
⏷ 13. What is a subquery, and how is it used?
⏷ 14. What is the difference between correlated and non-correlated subqueries?
⏷ 15. Can you use subqueries in SELECT, FROM, or WHERE clauses?
⏷ 16. What is an inline view?
⏷ 17. What are scalar and multi-row subqueries?
SQL Functions
⏷ 18. What is the purpose of the ROW_NUMBER() function?
⏷ 19. What are aggregate functions in SQL, and how are they used?
⏷ 20. How do you use string functions like CONCAT and SUBSTRING?
⏷ 21. What are date and time functions in SQL?
⏷ 22. Explain the purpose of mathematical functions in SQL.
Data Modification
⏷ 23. What is the difference between DELETE, TRUNCATE, and DROP?
⏷ 24. How do you handle upserts in SQL?
Indexes and Performance
⏷ 25. What is an index, and how does it improve performance?
⏷ 26. What are the types of indexes in SQL?
Indexes and Performance
⏷ 27. What is a clustered index, and how is it different from a non-clustered index?
⏷ 28. How do you analyze and optimize a query using EXPLAIN or EXPLAIN PLAN?
⏷ 29. What are common performance optimization techniques in SQL?
Transactions and Concurrency
⏷ 30. What is a transaction in SQL, and how do you use it?
⏷ 31. Explain the four isolation levels in SQL.
⏷ 32. What is a deadlock, and how do you resolve it?
Database Design and Normalization
⏷ 33. What is normalization, and why is it important?
⏷ 34. Explain the different normal forms (1NF, 2NF, 3NF, BCNF).
⏷ 35. What is denormalization, and when should it be used?
⏷ 36. What are database relationships (one-to-one, one-to-many, many-to-many)?
⏷ 37. What is the purpose of surrogate keys?
Advanced Topics
⏷ 38. What is a view, and how is it used?
⏷ 39. What are stored procedures and functions in SQL?
⏷ 40. What are triggers, and how do they work?
⏷ 41. Explain the difference between a materialized view and a regular view.
⏷ 42. What are common SQL extensions (e.g., PL/SQL, T-SQL)?
Security
⏷ 43. What are SQL injections, and how do you prevent them?
⏷ 44. How do you manage user privileges in SQL?
⏷ 45. What is row-level security in SQL?
⏷ 46. How do you encrypt data in SQL?
⏷ 47. Explain the role of roles and grants in SQL security.
Working with NoSQL and Newer Features
⏷ 48. How do you work with JSON data in SQL?
⏷ 49. What are window functions, and how do they work?
⏷ 50. What is Common Table Expression (CTE)?
⏷ 51. How do you work with recursive queries in SQL?
⏷ 52. Explain the purpose of partitioning in SQL.