SAP SE
Space efficient vector for columnar data storage

Abstract:

Disclosed herein are system, method, and computer program product embodiments for providing paged and compressed storage for column data, while maintaining existing access mechanisms for the data. In order to reduce an in-memory footprint for column data, columns may be stored in pageable format using page chains, and only those pages of the column data needed to resolve a query will be placed in memory, and evicted from memory when no longer needed. In order to further reduce the footprint for these columns, compression can be applied, and the compressed column data stored in the same pageable format using page chains. The compressed data includes a plurality of vectors, each of which is converted into pages and stored on the page chain with the others so that they can be efficiently retrieved during database retrieval operations.