Querying Continuous Time Sequences
Ling Lin, Tore Risch · 1998
Time sequences appear in various application domains. Many applications require time sequences to be seen as continuous where implicit values can be derived from explicit values by arbitrary user-defined interpolation functions. This paper describes the implementation of an extended SELECT operator, s*, that retrieves implicit values from a discrete time sequence under various user-defined interpolation assumptions. The s* operator is efficiently supported by an indexing technique termed the IP-index. Possible optimizations of the s* operator are investigated and verified by experiments on SHORE. The s* operator is applicable to any 1-D sequence data. 1 Introduction Modern Database applications involve large amounts of time sequences. Examples of time sequences appear in various application domains: 1) Scientific experiments such as temperature reading generated by sensors; 2) business applications such as stock price indexes or bank account histories; 3) medical data s...