A storage advisor for hybrid-store databases

With the SAP HANA database, SAP offers a high-perfor-mance in-memory hybrid-store database. Hybrid-store data-bases—that is, databases supporting row- and column-orien-ted data management—are getting more and more promi-nent. While the columnar management offers high-perfor-mance capabilities for analyzing large quantities of data, the row-oriented store can handle transactional point queries as well as inserts and updates more efficiently. To effectively take advantage of both stores at the same time the novel question whether to store the given data row- or column-oriented arises. We tackle this problem with a storage advi-sor tool that supports database administrators at this deci-sion. Our proposed storage advisor recommends the optimal store based on data and query characteristics; its core is a cost model to estimate and compare query execution times for the different stores. Besides a per-table decision, our tool also considers to horizontally and vertically partition the data and manage the partitions on different stores. We evaluated the storage advisor for the use in the SAP HANA database; we show the recommendation quality as well as the benefit of having the data in the optimal store with re-spect to increased query performance. 1