NoSQL DATA-SCIENCE-OPTIMIZE Practice Questions (Page 4)

Questions 16–20

1. 16expert · hard

   A social network uses a graph database to store user connections. They also need to generate daily recommendations for each user, which involves complex graph traversals. The team wants to offload the heavy computation to a Hadoop cluster. What is the best way to integrate the graph database with Hadoop?

   • AStore the graph data in HBase and use HBase's native graph capabilities
   • BExport the graph data to HDFS and use Apache Spark's GraphX library to run the traversal algorithms
   • CUse Apache Kafka to stream graph data to the Hadoop cluster and process it with MapReduce
   • DUse Apache Hive to run SQL queries on the graph database directly
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2. 17expert · hard

   A company uses a NoSQL database with eventual consistency to store user preferences. When a user updates their preferences, the change is replicated asynchronously. The company wants to ensure that a user always sees their own latest preferences, but other users can see slightly stale data. Which consistency model should they implement?

   • ARead-your-writes consistency
   • BCausal consistency
   • CStrong consistency
   • DEventual consistency
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4. 18application · medium

   A data engineering team stores raw clickstream logs in HDFS and uses Hive for batch processing. They now need to serve real-time user profiles to a web application with sub-millisecond latency. The profiles are stored as JSON documents and accessed by user ID. Which approach best integrates with the Hadoop ecosystem to meet this requirement?

   • AUse a standalone MongoDB cluster and export data from HDFS manually
   • BUse HBase as a key-value store, with the user ID as the row key, and load the profiles from HDFS into HBase via a MapReduce or Spark job
   • CUse Apache Kafka to stream profiles directly to the web application without any database
   • DStore the JSON profiles in HDFS and use Hive to query them on demand
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5. 19expert · hard

   A global e-commerce company uses a NoSQL database with eventual consistency to store product reviews. A user submits a review, and it is immediately written to the primary region. The user then refreshes the page and is routed to a secondary region that has not yet received the replicated write. The user does not see their review. The company wants to improve the user experience without sacrificing the availability benefits of eventual consistency. Which approach best addresses this issue?

   • AIncrease the replication frequency to reduce the window of inconsistency
   • BSwitch to strong consistency for all reads and writes
   • CImplement read-your-writes consistency by routing reads for a user to the region where their write was acknowledged
   • DUse a distributed cache to store recent writes and check it before reading from the database
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6. 20foundation · easy

   Which tool in the Hadoop ecosystem is commonly used to move data between Hadoop and NoSQL databases like HBase or Cassandra?

   • AApache Flume
   • BApache Oozie
   • CApache Ambari
   • DApache Sqoop
   Reveal Solution Discussion Select an answer first