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cassandranosql

Does the order of the columns in the partition key matter?

Considering the table below, does the order of the partition key a and b matter?

CREATE TABLE t (
  a varchar,
  b int,
  c text,
  PRIMARY KEY ((a,b))
);

If a have more unique elements, should it be in the first or last position?

Solution

  • The partition key as a whole uniquely identifies a partition in the cluster and gets hashed into a single token value regardless of how many columns there are in the composite partition key.

    How the columns are ordered does not matter since all columns are required to identify a single partition. Cheers!