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ARTs_EDB is based on memory database (MMDB) as the underlying support, relational database-based integrated real-time databases and active mechanism for active real-time embedded database management system, therefore, ARTs_EDB of these characteristics determine the structure of their data storage systems are also different from the a traditional relational database, ARTs-EDB adopted a "section" type of storage structure to achieve the right memory database storage and management, this structure makes ATRs_EDB become a well-functioning and efficient modern database management systems.Although the ATRs_EDB as a memory database, but also integrates a number of features (such as real-time and active mechanism) so that it can be applied in many areas, but, in order to make the function more ATRs_EDB perfect, that is, have to deal with temporal data features in the ATRs_EDB introduced two time dimension, namely, transaction time and valid time.We know that, in order to effectively ATRs_EDB storage of temporal data, we must construct the temporal data storage, data structure, thus the introduction of two time-related keywords Now with UC, which represents the effective time Now the current the time, UC said in the transaction time, until the tuple to change the time. After the introduction of these two keywords based on temporal data in real-world practical application of design four kinds of temporal data is stored in storage structure (tb, UC, vb, Now) (tb, UC, vb, ve) ( tb, te, vb, ve) (tb, te, vb, Now), which, tb, te, vb, ve transaction time, respectively, the start time and end time, effective time of the start time and end time. This storage structure is not only in people’s daily living habits, and can effectively reduce data redundancy, in large measure to save more memory space.Of temporal data in the storage structure in the ATRs_EDB finalized later on related to the query of temporal data for the problem, due to temporal data is stored and the structural peculiarities, the ordinary index structure can not be right temporal data, effective and accurate search, it must address the characteristics of temporal data to develop the structure appropriate to their own index. The TS-tree index is for the temporal data of 4 different types of storage structures designed for temporal data indexing. We know that, when temporal data is a valid time and transaction time, composed of two-dimensional nature of real-time state data are, therefore, TS-tree is a suitable two-dimensional data query index structure.Finally passed tests to demonstrate that the TS-tree index structure than the traditional index structures such as B + tree in the query efficiency advantage, and with the amount of data increases, the advantage will become even more apparent.
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