Design Of Object-Oriented Spatial Relational Database In GIS

Spatial data has much particularity. It has not only attribute feature as common objects but also spatial feature relevant to position. It can hardly express in relative model. So using object-oriented database to store spatial data is very important in theory and technologies. The more complex in data structure, the more superiority of it will be shown.This paper introduces object-oriented feature into relative theory of RDB and combines object-oriented technologies with relative theory. This paper puts forward a set of mapping theory of relation-object model. It not only conquers the disadvantage that relative theory is too simple but also stores and expresses object-oriented data in RDB. In this paper, emphases is centralized in the studies of conversion theory from relative model to object-oriented model described in UML.A study case of cadastral information system is given to explain all above theory in oracle. By those, we can establish an object-oriented spatial RDB system.This paper studies the realization method of one-to-one relation, one-to-multiple relation and multiple-to-one relation described in UML in RDB, respectively realizes them in oracle, and provides reader by SQL. This paper also studies on inheritance and congregation of classes and provides you with realization method. This paper makes a research on how to encapsulate method in oracle and provides reader with some examples. By those, objects defined in RDB can store method with other attributes. So objects in database can not only modify their own attributes by themselves but also communicate with outside objects by function method. In addition, this paper discusses how to inherit method in RDB and brings forward some feasible advice on method inheritance and realizes inheritance of method in oracle. To eliminate redundancy and decrease dependence, this paper brings forward two mode of object organization: derivation and reference. They are the effective way in organizing object.In a word, this paper makes a deep study on adding object-oriented features in RDB from theory and practice. It will make a large advance in development and revolution of spatial database.