DataStax Academy FAQ

DataStax Academy migrated to a new learning management system (LMS) in July 2020. We are also moving to a new Cassandra Certification process so there are changes to exam bookings, voucher system and issuing of certificates.

Check out the Academy FAQ pages for answers to your questions:


question

guzelcihad avatar image
guzelcihad asked ·

What is the bucket column in the video_interactions_by_user in KillrVideo?

Guys,

I am sorry for this question but I really don't know what does it mean and couldn't figure it out.

Can anyone tell me what bucket means and represents of what data in this table?

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data modelingds220
1613595644237.png (93.2 KiB)
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1 Answer

Erick Ramirez avatar image
Erick Ramirez answered ·

It's just a column to break up the partitions to make them smaller in size. It's just an example to illustrate how you can split the partitions into "buckets" to make them more manageable.

In the DS220 course example, it talks about the user having too many interactions with videos in the thousands. To reduce the number of rows in each partition, we add an arbitrary bucket column to make a composite partition key so we can manually control the size of each partition in the video_interactions_by_user table.

Again, the choice is completely arbitrary and is not a "natural key". It's just to show you ways to design tables. Cheers!

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