Design, Implementation, and Performance of the LHAM Log-Structured History Data Access Method

Numerous applications such as stock market or medical information systems require that both historical and current data be logically integrated into a temporal database. The underlying access method must support different forms of "time-travel" queries, the migration of old record versions onto inexpensive archive media, and high insert and update rates. This paper introduces a new access method for transaction-time temporal data, called the Logstructured History Data Access Method (LHAM) that meets these demands. The basic principle of LHAM is to partition the data into successive components based on the timestamps of the record versions. Components are assigned to different levels of a storage hierarchy, and incoming data is continuously migrated through the hierarchy. The paper discusses the LHAM concepts, including concurrency control and recovery, our full-fledged LHAM implementation, and experimental performance results based on this implementation. A detailed comparis...

• Type: Conference
• Year: 1998
• Where: VLDB
• Authors: Peter Muth, Patrick E. O'Neil, Achim Pick, Gerhard Weikum
• Keywords: Access Method, Database, Record Versions, Underlying Access Method, VLDB 1998