Introduction to Composite Columns

Composite columns in Apache Cassandra are useful for adapting some models and providing new indexing functionality, particularly for time series data. They help in efficiently accessing data by minimizing disk seeks and reducing overhead associated with large numbers of skinny rows. Composite comparators can be thought of as a comparator composed of several other types of comparators. Two forms of composite comparators are CompositeType and DynamicCompositeType, with the former being discussed in this text. The use of composite columns is demonstrated through an example involving timezone data for major cities in the United States. CompositeDataLoader can be used as a model for application-level parallelized bulk loading with the Hector API, while CompositeQuery class makes use of an auto-paging feature built into Hector to provide clean iteration semantics back up to the caller.