Studies Based On Relational Database's Multi-Layered XML Data Maintenance

Dramatic increase of net user quantity and system amount leads to surprising growth of enterprises, emails and commercial software as well as the complexity of relationship between data and data. XML schema is always chosen as the medium of data exchange between different applications, while relational database is usually selected as the storage form of data sources. What's the question is that low effect commonly appears during the process of updating because of complicated hierarchy of XML data elements. And it will also bring troubles to data backup when the amount of system data comes to be a large scale.Based on the questions we talked above, this paper is aimed to design a method that can avoid some unnecessary update during the data updating from XML files to database, which can be decreased times of database access, reduce the exchange time period and enhance efficiency of server. Besides, this thesis discusses some representation methods used for reducing data backup space and return old records to current version. The paper prime task is:Firstly, it is discussed the structure of XML data transmission in the application and specifies the functions of each constituent. Also, it talks about popular storage methods of XML files in databases. and heir good and bad points, finally, discussed two kind of mapping way between the XML data and the relational dataSecondly, it is discussed a data updating strategy, through this strategy can decrease database access times and improve the server utilization. A data backup method is also proposed and can be used to backup and restore system data visually.Thirdly, this paper is get to be well verified in the application "supporting environment of a city emergency resource sharing platform". During the contrast between traditional method and new strategy this paper gave it is clearly to see that it is suitable for most updating processes to add new fields in tables. What's more, it backups and restores the data visually, deduces data space and makes data management more convenient.