基于OCCI的空间数据库几何对象实现方法

Geometric Object Implementation of Spatial Database with OCCI

海量空间数据的高效访问和操作是 GIS平台和应用系统开发的核心技术。本文分析了 Oracle数据库管理系统所提供的访问接口 OCI、OCCI及对象类型转换工具 OTT的特性 ,基于 OCCI和 OTT技术提出了一种面向对象的访问及操作 SDO几何对象的方法 ,并通过实例讨论了实现过程。该方法利用 SDO几何模型作为 Oracle服务端的几何对象载体 ,在客户端通过继承 SDO几何对象实现自定义几何对象模型 ,避免了 SDO几何对象与用户定义几何对象之间的空间数据转换过程 ,有利于扩展自定义空间数据模型。同时 ,自定义几何对象可以充分利用Oracle Spatial提供的空间操作与整合功能 ,加速 GIS软件平台研发过程。

Accessing and manipulating the spatial data efficiently stored in the enterprise relational database management systems is an important task f or GIS platforms and engineering Among the interfaces provided by Oracle, Oracle Call Interface (OCI) and Oracle C++ Call Interface (OCCI) are welcomed for their outstanding advantages With a detailed analysis on OCI, OCCI and Object Type Translator (OTT), the authors set forward an object oriented method accessing and manipulating the SDO geometric objects in Oracle system with OCCI and OTT technologies, and conducted an experiment with Oracle 9i The method allows users to construct their own geometric model with inheritance from SDO geometric model, thus avoiding the spatial information transformation between SDO geometric objects and user defined geometric objects during uploading and downloading the spatial data Mo reover, the spatial operators and spatial aggregate functions of Oracle Spatial can be used sufficiently