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guruprasadb avatar image
guruprasadb asked ·

Will the data in two tables be in different physical partitions if they have the same partition key?

[FOLLOW UP QUESTION TO #10921]

If I have tables with the same partition key, will the data be in different physical partitions for Table2 and Table3 in such a scenario? Or if it maps to same partition number how will cassandra internally distinguish between the two tables?

partitioner
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1 Answer

Erick Ramirez avatar image
Erick Ramirez answered ·

I'm not sure what you mean by "different physical partitions" but I'll try my best to answer your question.

The partitions for 2 tables have no relation to each other regardless of whether they have the same partition key. When you read or write to a table, you are operating on a distinct, specific table in the database.

For example, these 2 write requests will write to 2 different tables even if their partition keys are identical:

INSERT INTO table2 (enterprise_id, ...) VALUES ('abc123', ...)
INSERT INTO table3 (enterprise_id, ...) VALUES ('abc123', ...)

The first query is writing to table2 which is a completely different table to table3 in the second query. The data is stored in different tables and one simply has nothing to do with the other. Cheers!

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