Things to Keep In Mind

The DataStax whitepaper "Data Modeling in Apache Cassandra™" provides a guide on choosing the right data model for your Apache Cassandra application in five steps. It highlights that while CQL resembles SQL, understanding how Cassandra stores data is crucial to avoid problems. Using an example of partitioning users into groups, it demonstrates the importance of using groupname as a partition key for fast lookup. The whitepaper also discusses the challenges of normalizing database schemas and recommends creating query-specific tables or using composite partition keys to reduce the number of rows per partition. Secondary indexes are another solution but should only be used when queries return tens or hundreds of rows at most, and when the indexed column has medium cardinality.