Abstract: Data dictionary(DD) is an important part of the database system design content,and it is a collection of data lists that describes the attributes,composition and structure of the data in the database.In the development process of some general-purpose information systems,designers and developers often encounter the problem of how to integrate and optimize existing heterogeneous data dictionaries.Due to the lack of industry data standards or business scope limitations,these existing data dictionaries differ significantly in data representation definition,data composition and structure design,but their data content is highly convergable.It takes a lot of time and resources to manually maintain a converged data dictionary.Based on the business background of grass-roots social grid governance,this paper aims at the pain points of heterogeneous data dictionary fusion in the development of grass-roots social governance promotion digital application,and studies the optimization methods and related technologies of he-terogeneous data dictionary fusion.The methods and techniques of data dictionary fusion are designed,which consider the completeness of data information and the integrity of data structure,such as semantic deduplication and disambiguation,keyword extraction,similarity calculation and table structure fusion.Based on the experimental verification of data dictionary fusion optimization of grass-roots social grid governance business,the fusion efficiency and effect are significantly improved compared with the traditional data dictionary fusion method.

Key words: Data dictionary, Database design, Edit distance, Similarity calculation, Grass-roots social grid governance