DataStax Cassandra Developer Certification Certification Questions and Answer (Dumps and Practice Questions)

Question : . In Cassandra insertions or updates of two or more rows in the same partition are treated as one write
operation.

1. True
2. False

Correct Answer : Get Lastest Questions and Answer :
Explanation: In Cassandra, a write operation is atomic at the partition level, meaning the insertions or updates
of two or more rows in the same partition are treated as one write operation. A delete operation is also atomic at the
partition level.




Question : If you are using write consistency level of QUORUM with a replication factor of

1. Cassandra will replicate the write to all nodes in the cluster and wait for acknowledgement from two
nodes.

2. Cassandra will replicate the write to all nodes in the cluster and wait for acknowledgement from one of
the nodes.

3. Access Mostly Uused Products by 50000+ Subscribers
nodes.

4. Cassandra will replicate the write to all nodes in the cluster and does not wait for acknowledgement from
two nodes.


Correct Answer : Get Lastest Questions and Answer :
Explanation: In Cassandra, a write operation is atomic at the partition level, meaning the insertions or updates
of two or more rows in the same partition are treated as one write operation. A delete operation is also atomic at the
partition level.

For example, if using a write consistency level of QUORUM with a replication factor of 3, Cassandra will replicate the write
to all nodes in the cluster and wait for acknowledgement from two nodes. If the write fails on one of the nodes but succeeds
on the other, Cassandra reports a failure to replicate the write on that node. However, the replicated write that succeeds on
the other node is not automatically rolled back.





Question : Which of the following is true ?

1. Cassandra uses client-side timestamps to determine the most recent update to a column.

2. Cassandra uses server-side timestamps to determine the most recent update to a column.

3. Access Mostly Uused Products by 50000+ Subscribers
to a column.

4. Cassandra uses user provided timestamps to determine the most recent update to a column.


Correct Answer : Get Lastest Questions and Answer :
Explanation: Cassandra uses client-side timestamps to determine the most recent update to a column. The latest
timestamp always wins when requesting data, so if multiple client sessions update the same columns in a row concurrently, the
most recent update is the one seen by readers.

Related Questions

---

Question : You have a website, which hosts various Books and books having attributes like title, author, publisher etc.
Which of the following component in ER diagram conceptually represent each book

1. Relationship

2. Entity

3. Access Mostly Uused Products by 50000+ Subscribers

4. It could be either Entity or Relationship



Question : Weak Entity type cannot exist without strong entity type (Assume they have relationship exist)

1. True
2. False


Question : Which all are the advantages of the conceptual data modeling?

1. Conceptual Data Modeling helps in collaboration between both technical and non-technical team members

2. Conceptual Data Modeling provides abstraction from the problem details

3. Access Mostly Uused Products by 50000+ Subscribers

4. 1 and 3

5. 1,2 and 3


Question : . You must define Constraint types in a conceptual data model?

1. True
2. False


Question : In conceptual data modeling Attribute types can be

A. key
B. composite
C. multi-valued
D. A and C
E. A,B and C


1. key

2. composite

3. Access Mostly Uused Products by 50000+ Subscribers

4. 1 and 3

5. 1,2 and 3



Question : In Cassandra, you will design tables based on Query ?

1. True
2. False