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Questions

https://www.edureka.co/blog/interview-questions/cassandra-interview-questions

Which of the following is not a feature of Cassandra?​

  • No single point of failure
  • High availability
  • ACID compliance
  • Linear scalability

Cassandra uses a master/slave architecture​

False

Cassandra supports multiple datacenters out of the box​

True

Which of the following statements about Cassandra is false?​

  • All nodes hold data and can answer queries
  • A master node determines who gets what data
  • Data is replicated on different nodes
  • Data is partitioned around the ring

With the CAP theorum, Cassandra is​

  • Available and partition tolerant
  • Consistent and partition tolerant
  • Available and consistent
  • None of the above

Replication Factor (RF) is how many copies of each piece of data should you have in your cluster​

True

Where is Replication Factor (RF) set in Cassandra?​

  • When creating a keyspace
  • When creating a table
  • On a per-query basis
  • In Cassandra configuration file

Hinted handoff is used when a node is down to replay all of the writes that occured​

True

Consistency level can be set for​

  • Read requests
  • Write requests
  • Both read and write requests
  • Is not configurable

Read and write speed is not impacted by the consistency level chosen​

False

Where is Consistency Level (CL) set in Cassandra?​

  • On a per-query basis
  • When creating a table
  • When creating a keyspace
  • Is not configurable

Any node in a cluster can service a write request​

True

What is the node that handles a request called?​

  • Leader node
  • Master node
  • Slave node
  • Coordinator node

The order for the write path in Cassandra is​

  • Commit log to SSTable to MemTable
  • Commit log to MemTable to SSTable
  • Commit log to MemTable to DiskTable
  • None of the above

Cassandra does not do any writes or deletes in place​

True

SSTables in Cassandra are not immutable​

False

Compaction is the process of​

  • Taking small SSTables and merges them into bigger ones.
  • Taking Memtables and merging them into SSTables.
  • Merging Memtables into larger Memtables.
  • Merging Memtables into larger Memtables.

"Last write wins" uses what to determine what data to return to client?​

  • Tombstones
  • Timestamps
  • Compaction
  • Coordinator

Partitions​

  • format data for CQL queries.
  • maintain a log of all executed queries.
  • optimize query-time joins keeping frequently queried rows together on disk.
  • group rows physically together on disk based on the partition key.

What is the role of the partitioner?​

  • It organizes the data together physically on disk.
  • It hashes the partition key values to create a partition token.
  • It retrieves partition data for a CQL query.
  • It physically separates rows into equal-sized partitions.

Partition key columns are optional if you have clustering columns​

False

What benefits do Clustering columns provide?​

  • Reading sorted data is a matter of seeking the disk head once.
  • They allow partitions to be spread over several drives.
  • You can change the clustering criteria on a table at any time.
  • The optimize writes by shuffling the data on disk at write time.