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数据库技术的萌芽从60年代中期产生。到1969年IBM 公司研制开发数据库管理系统的商品化软件 IMS(Information Management System)。IMS 的数据模型是层次结构的,它的基本数据结构是由若干相关联的片段组成的一个层次结构,或者称为树,一个 IMS 的整体数据模型是若干树的集合。IBM 公司还先后提供了与 IMS有关的一组软件产品,如数据字典、查询接口(交互的和批处理的)、应用生成器、设计辅助工具、测试差错程序、性能测量和调优工具等。同时美国数据系统语言协会下的数据库任务组(DBTG)对数据库方法进行了系统的研究,在其报告中确立了数据库系统的许多概念、方法和技术。DBTG所提议的方法是基于网状结构的,是数据库网状模型的
The germ of database technology emerged from the mid-1960s. By 1969, IBM Corporation developed the commercialized database management system IMS (Information Management System). The data model of IMS is a hierarchical structure. Its basic data structure is a hierarchical structure composed of several related fragments, or called a tree. The overall data model of an IMS is a collection of several trees. IBM has also provided a set of software products related to IMS, such as data dictionary, query interface (interactive and batch), application generator, design aids, test error programs, performance measurement and tuning tools. At the same time, the Database Task Group (DBTG) under the U.S. Data Systems Language Association conducted a systematic study of the database methods and established many concepts, methods, and techniques of database systems in its reports. The method proposed by DBTG is based on a mesh structure and is a database mesh model.