Transaction-Time Indexing

DEFINITION A transaction-time index is a temporal index that enables fast access to transaction-time datasets. In a traditional database, an index is used for selection queries. When accessing transaction-time databases, selection queries also involve the transaction-time dimension. The characteristics of the transaction-time axis imply various properties that such temporal index should have to be efficient. As with traditional indices, the performance is described by three costs: (i) storage cost (i.e., the number of pages the index occupies on the disk), (ii) update cost (the number of pages accessed to perform an update on the index; for example when adding, deleting or updating a record) and (iii) query cost (the number of pages accessed for the index to answer a query).