Maintaining Temporal
نویسندگان
چکیده
An important use of data warehousing is to provide temporal views over the history of source data that may itself be non-temporal. While recent work in view maintenance is applicable to data warehous-ing, only non-temporal views have been considered. In this paper, we introduce a framework for maintaining temporal views over non-temporal information sources in a data warehousing environment. We describe an architecture for the temporal data warehouse that automatically maintains temporal views over non-temporal source relations, and allows users to ask temporal queries using these views. Because of the dimension of time, a materialized temporal view may need to be updated not only when source relations change, but also as time advances. We present incremental techniques to maintain temporal views for both cases.
منابع مشابه
Prefrontal contributions to domain-general executive control processes during temporal context retrieval.
Neuroimaging studies have reported increased prefrontal cortex (PFC) activity during temporal context retrieval versus recognition memory. However, it remains unclear if these activations reflect PFC contributions to domain-general executive control processes or domain-specific retrieval processes. To gain a better understanding of the functional roles of these various PFC regions during tempor...
متن کاملMaintaining Semi-structured Spatio-Temporal Data Based on Nesting-Relation-Oriented Model
semi-structured spatio-Temporal data has become prevalent with growth of GIS. In this paper, we propose to use “Nested” natural of spatio-Temporal data to storing & maintaining it efficiently in an Object-Relational Database based on Nesting-Relation-Oriented data Model– one of N1NF database. This model not only reflects the nested structure of semi-structured spatio-Temporal data, but also dis...
متن کاملRelative temporal representations in Pavlovian conditioning.
The transfer of relative temporal representations was assessed in a series of three experiments. In each experiment, rats (Rattus norvegicus) received one set of conditioned stimulus (CS) and intertrial interval (ITI) durations in Phase 1 and another set in Phase 2. The ratio between the CS and ITI intervals was either changed or maintained across phases. On the hypothesis that relative tempora...
متن کاملWorking memory and amnesia: the role of stimulus novelty.
Despite the traditional view that damage to the hippocampus and/or surrounding areas of the medial temporal lobe (MTL) does not impair short-term or working memory (WM), recent research has shown MTL amnesics to be impaired on WM tasks that require maintaining a small amount of information over brief retention intervals (e.g., maintenance of a single face for one second). However, the types of ...
متن کاملSatisfying Multiple Constraints in Real-Time Database Systems
Real-time database systems, such as military command, control and communication, avionics, radar tracking, and managing automated factories, have timing constraints and temporal consistency constraints. The timing constraint requires a transaction to be completed by a specified deadline. The temporal consistency constraints require that data read by a transaction be up-to-date. In such environm...
متن کامل