DOCUMENT DATABASES — Learn free

Self-check

Questions 1–10 of 10

1. How do document databases store data?
Question 1A. As JSON-like documents that can contain nested fields, arrays and variable structuresB. As rows and columns in normalised tablesC. As nodes and edgesD. As owner–member sets with pointersE. As columns grouped into families and partitioned by key
2. What does a single document typically represent in a document database?
Question 2A. One column of a tableB. One business object, such as an entire loan applicationC. One transaction log entryD. One index entryE. One relationship between two entities
3. In the MongoDB loan example, how is the repayment history represented inside the loan document?
Question 3A. As a foreign key to a Repayment collectionB. As a comma-separated string fieldC. As an array of Repayments, each with its date and amountD. As a nested LoanOfficer objectE. As a separate top-level document per instalment
4. Why do document databases align naturally with API payloads?
Question 4A. Because they enforce strict schemasB. Because they require joins before serving dataC. Because they store data in relational tablesD. Because the data is already in JSON formatE. Because they use SQL for queries
5. Why can adding a new field to a document database be done easily?
Question 5A. Because every field is stored as a separate tableB. Because new fields are ignored until a migration runsC. Because document databases are read-onlyD. Because documents cannot contain nested fieldsE. Because the schema is flexible, so new fields need no costly table migrations or rigid schema alterations
6. What consistency challenge arises when a customer's details are embedded in several loan documents?
Question 6A. Ensuring that a change such as an updated credit score is applied everywhere becomes more complex than in a relational databaseB. The customer can no longer be uniquely identifiedC. The loan documents cannot be retrieved in a single readD. The credit score must be stored as a stringE. The documents must be normalised to 3NF first
7. Which of the following is NOT listed as a strength of document databases?
Question 7A. Schema flexibility and developer friendlinessB. Strong global consistency guarantees comparable to relational systemsC. Natural handling of semi-structured and nested dataD. Close alignment with modern web and mobile architecturesE. Support for agile development cycles
8. In the comparison of relational and document models for loan approval, what is the relational model best for?
Question 8A. Agility and speed of developmentB. Serving data directly to apps and APIsC. Consistency, integration and complex queriesD. Eliminating all joinsE. Storing nested arrays
9. How does the relational loan approval model assemble a full loan record, compared with the document model?
Question 9A. Both retrieve the record in a single readB. The relational model embeds all data in one rowC. The document model requires joins across collectionsD. The relational model requires multiple joins across Customer, Officer, Branch and Repayment tables, whereas the document model retrieves everything in a single readE. Neither model can produce a full loan record
10. What is the key difference between Object-Oriented Data Modelling and document data modelling?
Question 10A. Document databases cannot represent nested objectsB. Object-oriented models use flat tables while documents are nestedC. Object-oriented modelling is newer than document modellingD. Document databases store methods alongside dataE. Object-oriented modelling bundled logic with data inside the database, whereas document databases keep only the data representation and leave logic in application code