Ace Your Interview: Advanced System Design Solutions for Database Performance Quiz

1. Question 1

   When designing a system that frequently reads the same small subset of data, which of the following approaches is most effective for reducing the load on the primary database and latency for end-users?

   1. A. Implementing an in-memory cache between the application and database (e.g., a caching layer)
   2. B. Increasing the database backup frequency
   3. C. Using only vertical scaling of the database server
   4. D. Adding more secondary indexes to the database tables
   5. E. Sharding the database with random sharding keys

2. Question 2

   Given a write-heavy application where database locking leads to high contention and decreased throughput, which solution is best for minimizing lock contention while preserving data integrity?

   1. A. Implementing row-level locking instead of table-level locking
   2. B. Increasing the number of read replicas
   3. C. Adding covering indexes to all columns
   4. D. Splitting the network into multiple subnets
   5. E. Using eventual consitency for all transactions

3. Question 3

   Suppose you need to support rapid analytical queries on very large, time-stamped log data while maintaining fast write speeds. Which system design approach is most appropriate?

   1. A. Partitioning the log data by time ranges using horizontal partitioning (time-based sharding)
   2. B. Putting all logs into a single unpartitioned table
   3. C. Using only normalization to 5th normal form
   4. D. Utilizing vertical sharding based on log message types
   5. E. Indexing only the primary key column

4. Question 4

   A system has frequent slow queries due to multiple table joins on large tables with no enforced relationships. What system design modification would most likely provide a significant performance boost in this scenario?

   1. A. Denormalizing the related tables to reduce join operations
   2. B. Adding foreign keys without indexes
   3. C. Normalizing the tables further
   4. D. Increasing the server’s RAM only
   5. E. Disabling all constraints on the tables

5. Question 5

   In a geo-distributed application, ensuring both low latency and strong consistency for cross-region database writes is challenging. Which design pattern most likely achieves the best balance between the two requirements?

   1. A. Employing a quorum-based consensus protocol for distributed transactions
   2. B. Replicating data asynchronously to all regions
   3. C. Writing only to the primary region at all times
   4. D. Using sticky sessions at the application layer
   5. E. Maintaining separate, isolated databases per region