Database Systems for Efficient Access to Tertiary Memory

Tertiary storage devices have long been in use for storing massive amounts of data in le-oriented mass storage systems. However, their use in database systems is relatively new. Database systems associate more structure to the data than just raw sequence of bytes. Hence if they are allowed control of the tertiary memory devices, they can greatly reduce access cost by doing more informed caching, query optimization and query scheduling. However, most conventional database systems are designed for data stored on magnetic disks. Accesses to tertiary storage devices are slow and non-uniform compared to secondary storage devices. Therefore, inclusion of tertiary memory as an active part of the storage hierarchy requires a rethinking of conventional query processing techniques. In this project, our aim is to design a database system that can use its knowledge of the layout of data on storage devices to increase the speed of running queries.