| 1 | What is database normalization, and why is it an important concept in schema design? SQL Server › Normalization | SQL Server | Normalization | Beginner |
| 2 | What practical problems, such as update anomalies, can occur in a poorly normalized database, and how does normalization address them? SQL Server › Normalization | SQL Server | Normalization | Intermediate |
| 3 | What is database normalization, and what specific problems can over-normalization or under-normalization cause? Node.js › Databases | Node.js | Databases | Intermediate |
| 4 | How should you structure Firestore data using subcollections and denormalization to design efficient queries, given that Firestore does not support traditional relational joins across separate collections? Flutter › Cloud Firestore & Firebase Storage | Flutter | Cloud Firestore & Firebase Storage | Advanced |
| 5 | What is the first normal form, and what specific rule does it require a table to follow? SQL Server › Normalization | SQL Server | Normalization | Beginner |
| 6 | What is the second normal form, and how does it build on the requirements of the first normal form? SQL Server › Normalization | SQL Server | Normalization | Intermediate |
| 7 | What is the third normal form, and what kind of dependency does it specifically eliminate? SQL Server › Normalization | SQL Server | Normalization | Intermediate |
| 8 | When would it make sense to intentionally denormalize a database design, and what specific tradeoffs come with that decision? SQL Server › Normalization | SQL Server | Normalization | Advanced |
| 9 | How would you approach normalizing an existing, poorly designed legacy database without breaking the applications that currently depend on it? SQL Server › Normalization | SQL Server | Normalization | Advanced |
| 10 | What are aggregate functions in SQL Server, and what are the most common ones? SQL Server › Aggregate Functions & GROUP BY | SQL Server | Aggregate Functions & GROUP BY | Beginner |
| 11 | What is a primary key constraint, and why is it important for a database table? SQL Server › Constraints (Primary Key, Foreign Key, Check & Unique) | SQL Server | Constraints (Primary Key, Foreign Key, Check & Unique) | Beginner |
| 12 | What is a foreign key constraint, and how does it help maintain data integrity between two related tables? SQL Server › Constraints (Primary Key, Foreign Key, Check & Unique) | SQL Server | Constraints (Primary Key, Foreign Key, Check & Unique) | Beginner |
| 13 | What are the most commonly used data types in SQL Server, and when would you use each one? SQL Server › Data Types & Schema Design | SQL Server | Data Types & Schema Design | Beginner |
| 14 | What does it mean to unpivot data, and how is it essentially the opposite operation of pivoting? SQL Server › Pivoting & Unpivoting Data | SQL Server | Pivoting & Unpivoting Data | Beginner |
| 15 | How do you choose an appropriately sized data type for a column to balance storage efficiency with future flexibility? SQL Server › Data Types & Schema Design | SQL Server | Data Types & Schema Design | Intermediate |
| 16 | How do cascading actions work with foreign key constraints, such as ON DELETE CASCADE, and what risks come with using them? SQL Server › Constraints (Primary Key, Foreign Key, Check & Unique) | SQL Server | Constraints (Primary Key, Foreign Key, Check & Unique) | Advanced |
| 17 | How do you design a schema to properly handle a many to many relationship between two entities, such as students and courses? SQL Server › Data Types & Schema Design | SQL Server | Data Types & Schema Design | Advanced |
| 18 | What factors should guide the decision to denormalize a schema for performance reasons, and what tradeoffs come with that decision? SQL Server › Data Types & Schema Design | SQL Server | Data Types & Schema Design | Advanced |
| 19 | How would you use MERGE to implement a slowly changing dimension pattern in a data warehouse, tracking historical changes to a record over time? SQL Server › Merge Statement (Upsert) | SQL Server | Merge Statement (Upsert) | Advanced |