how many partition key for a Cassandra table? -

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partition key cassandra table?

in customer table customerid partition key?

suppose have 1 million customers in year have 1 million partitions

after 10 years have 10 million customers or more ... have 10 million paritions

so question ? 1) if want read customers table (10 million partition) affect read performance ?

note : in single partition may have 50 100 columns ?

you have right idea in you'll want use data modeling create multi-tenant environment. caveat you're not going want full table/multiple partition scans in cassandra retrieve data. it's pretty documented why, anytime have highly distributed environment, want minimize amount of network hops, data shuffling, etc. can't fight physics :)

anyways, sounds reporting type of use case - you're going need use spark or type of map , reduce efficiently report on multiple partitions this.


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