US Patent 9633073 Distributed data store for hierarchical data

A computing resource service provider may store user data in a distributed data storage system. The distributed data storage system may contain one or more storage nodes configured to store hierarchical data in one or more data stores such as a column data store. Data in the data stores may be compressed or otherwise encoded, by a storage optimizer, in order to reduce that redundancy in the hierarchical data stored in the one or more data stores. Responses to user queries may be fulfilled based at least in part on data stored in the one or more data stores. A query processor may scan multiple different data stores across various storage nodes in order to obtain items responsive to the user query.