Statistical queries on historical relational databases

There has been much attention given recently to the task of extracting statistical information and interesting features from historical relational databases with the more pragmatic aim of Finding trends in the evolution of temporal data, Analysing the past values of time sequence data to detect changes in the behaviour of historical data, Measuring serial dependence in the data sequence, and Discovering repeating appearance of interesting similar patterns and their cycles. Though there are many ways to model historical relational databases and associated query languages, the widely accepted approach is to extend the relational database concept and SQL language to temporal dimension. We follow this approach and augment some operators to the existing facilities for performing data analysis and statistical queries on the time sequence data generated from historical relational databases.