Research On Inderminate Direction Relations Query

Spatial database is a complex system which refers to the object spatial characteristics. In spatial database, direction relations'research and its application to the query language have become one of the important areas of Spatial database development. Direction relations in spatial objects mainly include certainty and uncertainty directions of the relation. At present, it has already had a very deep research on the direction of relation between the object model, predicates and query. The research on uncertainty direction of relation is less than certainty.The uncertainty is the common characteristic of many spatial data. It is widely found in the application of spatial database systems. Uncertainty of the direction of relation is mainly caused by the apparent uncertainty of the objective world of spatial data and the direction of the relationship between people's understanding of space ambiguity. The expression, approach and the application in the query language of uncertain direction of relation must be a problem to face. This article aims to study uncertainty in the direction of inquiries.Uncertain direction of queries in the study of spatial database is very important. The representation model that has been existed and index structure has been studied and compared in this paper that describes the system of spatial data, based on the direction of relation, with the direction of the relationship between matrix model and check the direction of R tree research. Vague set is used at the same time in the uncertainty representation, and it has carried on the reasoning and exposition of uncertain direction of the core content of the query - query predicates for, making more spatial directions check the accuracy.At first, it has in-depth analyzed and studied the relationship between the direction of the existing models, compared the advantages and disadvantages of all kinds of the direction of models, and proposed the uncertain direction of the relational model of Vague sets against the spatial database uncrtainty of the direction of the query. And using the direction of the relationship between Vague sets matrix, it has also analyzed the uncertainty attached to spatial objects with the direction of the relationship between the degree. Then it discusses the spatial object and its MBR mapping relations between the direction of the predicate, and the mapping application based on the certainty of the direction of the relationship between R tree query algorithm. Certainty the direction of search algorithms is the foundation of the uncertainty in search algorithms.Finally, the uncertainty in the direction of the relationship between the direction of the predicate is derived, and the direction of the relationship between Vague sets matrix model is applied to the uncertainty in the direction of the query and put forward the boundary between the uncertain direction of the object instances of queries and algorithms. And the test platforms to study is built to study its performance and features. Experiments show that, Vague Sets based on the direction of the direction of the relationship matrix model query algorithm reduces the uncertainty. The research projects have great significance in the direction of the relationship between the space of uncertainty and its technological development.