Unit 1: Introduction to NoSQL and MongoDB - Practice Quiz

1 What does the term NoSQL commonly mean?

2 Which feature is commonly associated with NoSQL databases?

3 How is data primarily organized in a traditional SQL database?

4 Which scaling approach is commonly associated with NoSQL databases?

5 What type of database is MongoDB?

6 Which format does MongoDB use internally to store documents?

7 What does the letter C represent in the CAP theorem?

8 What does partition tolerance mean in the CAP theorem?

9 How does a key-value database primarily store data?

10 Which operation is fundamental to retrieving data from a key-value database?

11 How does a column-oriented database primarily organize data?

12 Which workload commonly benefits from column-oriented storage?

13 What is the basic data unit in a document database?

14 What is a group of MongoDB documents called?

15 Which elements are central to a graph database?

16 What is the main purpose of a MongoDB replica set?

17 What is sharding in MongoDB?

18 What is MongoDB Community Edition?

19 Which MongoDB tool provides a graphical interface for exploring data?

20 What is MongoDB Atlas?

21 An online platform stores user profiles whose attributes vary significantly between users and change frequently. Why might a NoSQL database be suitable for this workload?

22 A web service must distribute a rapidly growing dataset across several commodity servers. Which NoSQL capability most directly supports this requirement?

23 A banking system processes transfers that must update several related accounts atomically and enforce strict relational constraints. Which database approach is generally the most natural fit?

24 An application repeatedly reads complete customer profiles, including addresses and preferences, but rarely queries those components independently. Which design is most appropriate?

25 A MongoDB collection contains product documents with different optional specifications. What happens when a new document includes a field that earlier documents do not have?

26 In a MongoDB document, which field serves as the required unique identifier within a collection?

27 During a network partition, a distributed database rejects some requests rather than return potentially inconsistent data. Which CAP properties is it prioritizing?

28 A distributed shopping-cart service continues accepting updates on both sides of a network partition and reconciles conflicts later. Which CAP trade-off does this behavior represent?

29 A gaming service must retrieve a player's session using a unique session token, with no need to query fields inside the session value. Which database model best matches this access pattern?

30 Why is a key-value database usually inefficient for finding all stored values whose internal city field equals Pune?

31 An analytics query calculates the average salary from a table containing hundreds of columns but millions of rows. Why can column-oriented storage improve this query?

32 Which workload is generally the best match for a column-oriented database?

33 An order and its line items are normally created, retrieved, and deleted together. In a document database, which model is typically most appropriate?

34 A publisher document refers to thousands of books, and each book is frequently queried and updated independently. Which document-modeling choice is most suitable?

35 A fraud-detection system must identify accounts connected through up to four layers of shared devices and transactions. Why is a graph database appropriate?

36 In a MongoDB replica set, the current primary becomes unavailable. What is the expected response when a majority of voting members can still communicate?

37 In a sharded MongoDB deployment, which component routes a client query to the appropriate shard or shards?

38 After installing MongoDB Community Edition, a developer can launch mongosh, but the connection to mongodb://localhost:27017 fails. Which check is most appropriate first?

39 A developer wants a repeatable command-line operation that returns active users from the users collection. Which mongosh command is appropriate?

40 An Atlas cluster is running, but a developer's local application cannot connect even though the username and password are correct. Which Atlas configuration should be checked first?

41 A rapidly growing application stores user activity events with fields that vary by event type. The application must ingest events from many regions and continue accepting writes during temporary network partitions. Which design most directly reflects a NoSQL motivation?

42 An order-processing system requires multi-row constraints, complex joins, and strict serializable transactions across inventory, payment, and shipment records. Which conclusion is most defensible?

43 A MongoDB collection contains customer documents whose optional fields differ by customer type. Which statement best describes the practical implication of this model?

44 During a network partition, a distributed database continues returning responses from both sides, but some responses may not reflect the latest write. Which CAP trade-off is being chosen?

45 A team claims that a database is both highly available and strongly consistent because it is deployed on a cluster. What is the most accurate critique?

46 A session service retrieves values only by exact session identifier and requires extremely low-latency reads at massive scale. Which data model is the most natural fit?

47 A key-value database is performing poorly because clients frequently need all products matching category, price range, and availability. What is the primary modeling issue?

48 An analytics workload scans several billion records but usually reads only three of hundreds of attributes and aggregates them by time range. Why is a column-oriented design advantageous?

49 Which workload is least appropriate for a column-oriented database optimized for analytical scans?

50 A blog application always displays an article together with its author summary and recent comments. The embedded data remains bounded and is updated with the article. Which modeling choice is most appropriate?

51 A MongoDB document would contain an ever-growing array of millions of sensor readings, while users query readings independently by sensor and time. What is the strongest design correction?

52 A fraud system must repeatedly discover short paths among accounts, devices, cards, and transactions, where relationship types and traversal depth matter. Which model is most suitable?

53 A graph database is not automatically the best choice merely because an application contains relationships. Which factor most strongly supports choosing a graph model?

54 In a MongoDB deployment, which component is primarily responsible for routing client operations to the appropriate shards in a sharded cluster?

55 A replica set has one primary and two secondaries. The primary becomes unreachable, and the secondaries can communicate with each other. What condition is most important for automatic election of a new primary?

56 After installing MongoDB Community Edition, the server process exits immediately when started manually. Which diagnostic action is most appropriate first?

57 A developer can run the MongoDB shell but receives a connection-refused error when connecting to localhost. Which explanation is most likely?

58 A developer wants to reproduce a complex Compass filter in an automated deployment script. Which approach best preserves repeatability?

59 A query works in Compass but fails in mongosh because a field contains a date. What is the most likely issue?

60 An Atlas cluster is reachable from a developer laptop but not from an application server in the cloud. Which Atlas configuration should be investigated first?