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

Question :You have been given below logical table detail.


comments_by_user_id
user_id K
comment_date C
course_id C
user_email S
comment
course_name
description
Each user can post on average 1000 comments. SO what would be the number of values per partition we can expect.



1. 301
2. 300
3. Access Mostly Uused Products by 50000+ Subscribers
4. 100

Correct Answer : Get Lastest Questions and Answer :
Explanation: Nv = Nr * (Nc – Npk – Ns) + Ns

= 1000 * (7-3-1)+1
= 1000 * (3)+1
= 3001





Question : You have following table designed

Course_By_Author
Author_id K
Course_id C
Title
description

For each author_id, you will be copying entire course detail again. Assuming each course is created by 5 author.
Hence, each course detail will be copied 5 times. Is this an issue ?


1. Yes
2. No
3. Access Mostly Uused Products by 50000+ Subscribers


Correct Answer : Get Lastest Questions and Answer :
Explanation: This should not be an issue, we are copying data 5 times (max number of authors). And here growth is
constant 5 times. So it is ok.




Question : You have been given below conceptual data model

And you have below Access pattern, which of the following is valid table design

where rating=? and publish_date=?


1. A
2. B
3. Access Mostly Uused Products by 50000+ Subscribers
4. D

Correct Answer : Get Lastest Questions and Answer :
Explanation: In this case we know, both the rating and publish_date are equality operator. Hence, need to be part
of primary key. Course_name is enough to uniquely identify the course, hence we need it to course_name.

Related Questions

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Question : You have been given below relationship for the HadoopExam Inc employee


Now find the correct table design for given query access pattern?

Where employee_id=?



1. A
2. B
3. Access Mostly Uused Products by 50000+ Subscribers
4. D


Question : You have been given below conceptual data model for HadoopExam on-demand training access.


Please design logical table, which represent below query?

Query : Find the course_list for a given owner and will be ranged based on update_time (sort course_list by recently updated
first)




1. A
2. B
3. Access Mostly Uused Products by 50000+ Subscribers
4. D


Question : You have been given below conceptual data model for HadoopExam on-demand training access.



Please design logical table, which represent below query?

Query : Find all course_channels subscribed by a subscriber (sort course_channel by ascending order)



1. A
2. B
3. Access Mostly Uused Products by 50000+ Subscribers
4. D


Question :You have been given below logical table detail.


comments_by_user_id
user_id K
comment_date C
course_id C
user_email S
comment
course_name
description
Each user can post on average 1000 comments. SO what would be the number of values per partition we can expect.



1. 301
2. 300
3. Access Mostly Uused Products by 50000+ Subscribers
4. 100


Question : You have following table designed

Course_By_Author
Author_id K
Course_id C
Title
description

For each author_id, you will be copying entire course detail again. Assuming each course is created by 5 author.
Hence, each course detail will be copied 5 times. Is this an issue ?


1. Yes
2. No
3. Access Mostly Uused Products by 50000+ Subscribers



Question : You have been given below conceptual data model

And you have below Access pattern, which of the following is valid table design

where rating=? and publish_date=?


1. A
2. B
3. Access Mostly Uused Products by 50000+ Subscribers
4. D