CN103809946A

CN103809946A - Method for integrating heterogeneous database based on XML (extensible markup language) and middleware

Info

Publication number: CN103809946A
Application number: CN201210446237.3A
Authority: CN
Inventors: 袁帅
Original assignee: ZHENJIANG HUAYANG INFORMATION TECHNOLOGY CO LTD
Current assignee: ZHENJIANG HUAYANG INFORMATION TECHNOLOGY CO LTD
Priority date: 2012-11-09
Filing date: 2012-11-09
Publication date: 2014-05-21

Abstract

The invention discloses a method for integrating a heterogeneous database based on an XML (extensible markup language) and middleware, and provides a new solution for realizing integration of the heterogeneous database based on the XML and the middleware. The method comprises the following steps: establishing a central database, and integrating all data, needing to be shared, in the heterogeneous database; adopting the XML as a data transmission format; constructing a communication framework between the heterogeneous database and the central database by using a Web application server (a BEA Web Logic Server) so as to ensure the safety and reliability of communication.

Description

A kind of integrated method of heterogeneous database based on XML and middleware

Technical field

A kind of integrated method of heterogeneous database based on XML and middleware mainly relates to the data storage technology in computer realm.

Background technology

Heterogeneous database is integrated is one had both had close ties with various databases, was different from again the new field of various databases.Its goal in research is the database of the multiple different structures to physically distributing, at the base that affects as few as possible local autonomy

On plinth, structure has the global data base of the needed transparency of user, to realize sharing and transparent access of data.

Summary of the invention

Retrieve and there is no to find the application materials about this system aspects by national patent.

Heterogeneous database integrated model based on XML and middleware, by existing each dispersion of enterprise or unit, independently, heterogeneous system couples together by middleware, forms an organic whole, generates a central database.Between them, realize the exchange of data and sharing of resource by be used as unified data layout with XML.Separate between original each system of enterprise, interface is different, and data layout is different.Model extracts the delta data in each subsystem, delta data in tables of data is converted to unified data layout XML file by client-side program, be transferred to server by JMS, then by serve end program receipt message, by data integration in central database.

(1) subsystem database

Under the different operating system platform that enterprise is existing, applying, different relational database management systems, it is all protected

Holding each contented relative independentability and autonomy, as Oracle, SQLServer, MySql, Access etc., access by JDBC, is the information source that we want integrated data.By trigger at any time record data change and write in the respective table of establishment.

(2) client tier

The function of this level is: access subdata base system by JDBC, and the data that change with Java timer timing extraction,

By XML analytical tool, the data of the renewal of each database are converted to XML document, and XML document is packaged into and is applicable to the message that JMS transmits, send to the queue of JMS theme by JMS client transmission program.

Because JMS does not define XML type of message, transmit XML message by JMS, at present general way is using LXM as a TextMessage or XML sequence is turned to a DOM object transmits.Experimental results show that, the former transmission efficiency is higher, therefore the model proposing is herein also that XML is encapsulated in TextMessage and is transmitted, so say above and eight L document package is dressed up and is applicable to message that JIIS transmits and is actually XML document is converted to text message TextMessage.The time of timer can be set according to actual conditions.Such as: if can be upgraded in time for central database, can be decided to be to update status the above operation of execution that each minute checks database the time, so the concrete function that this level is realized can be summarized as follows: delta data in timing extraction subdata base system: the XML document that is converted to consolidation form with XML analytical tool; XML document is converted to the text message transmission of going forward side by side.

(3) middleware layer

This level mainly, by the JMS server that configures in application server middleware BEA WebLogic and message subject or to row, is realized the message transmission of client application and central server end application program.The concrete function of this layer of realization is exactly the communication complexity of shielding bottom, maintain message subject or the queue of foundation, completes] function of the sending and receiving message of MS server.JMS server is the core of whole model, is the medium of each application system swap data, and it guarantees asynchronism, persistence and the reliability of message communicating.

(4) central database client

Whether the major function of this level is: message queue or the theme of JMS server just monitored in the operation of this client-side program always, have message to arrive.If do not have message just to monitor always, if there is message to arrive, carry out mutually deserved processing.Because we communicate by text message TextMessage, thus after receiving text message, be just converted to XML document, by XMI.Document is converted to the XML document corresponding to central data base system according to the data pattern mapped file between central database and subdata base, and this XML document is write in central database.Its specific implementation content can be described below: monitoring information; Receive message and be converted to XML document; The XML document obtaining is converted to the XML document corresponding to central data base system data by mapped file; XML document after conversion is write in central database by analytical tool.

(5) central database

Central database is to need shared unified information platform, needs shared information to be all stored in this.It is further to count

Provide unified basis according to excavation, information sharing etc.

Model flow process:

(1) subdata base system changes, and the trigger of establishment is recorded in the data that change in corresponding table;

(2) client-side program timing arrives, and reads the table that record data change, and has data to exist, and extracts delta data, is converted into XML document;

(3) XML document is converted to TextMessage, sends to] in the theme or queue of MS server;

(4) server end of monitoring this theme or queue receives this message, by corresponding crossover tool, the TextMessage message parse receiving is become to XML document or DOM object;

(5) XML document obtaining is converted to the XML document corresponding to central data base system data by mapped file;

(6) analyzing XML file, utilizes XML file data information updating central authorities shared data bank, finally realizes the integrated shared and synchronous refresh of heterogeneous database.

In implementation model, data layout is changed mutually:

Data between heterogeneous database management system can not direct interaction, in order to address this problem, we adopt XML as the data layout that represents data and transmission data, shielding isomerism, easily realize cross-platform integration: although adopted the form of XML, but how the delta data in database is converted to XML form, just becomes the emphasis of model realization.Because JMS does not define XML type of message, transmit XML message by JMS, conventionally transmit with TextMessage, so the conversion of XML form and text message format is also most important.Meanwhile, between each heterogeneous database distributing and between central shared data bank, certainly there is the inconsistency of data structure and data type, how to complete data structure and close the conversion of data type, also become the key of model realization.In a word, the relevant difficult point that is converted into this model realization of relevant a series of data layout in implementation model how.

This adopts Jdom technology to complete the format conversion between tables of data and XML form, by the outputString method of utilizing xmloutputterl311 class, dom is set to document, becomes text message.

Between central database and each subdata base, synchronize:

Realize heterogeneous database integrated, be exactly at the Cong Chushang that keeps each subdata base system relative independentability and autonomy, baby data transmission shared needs to central database, so how to realize between central database and each subdata base, synchronize most important.Briefly, be exactly after central Database, after in the subdata base of distribution, data change, the corresponding data of central database should change thereupon.

Realize this point, conventionally can adopt in two ways: be one, update all, in the time that synchronizing cycle, (what in model realization, we used is timer) arrived, subdata base data message is all sent to central database end by we, upgrade central database according to it, synchronous to realize; Because early stage database adopts Access more, and Access does not exist storage hair device, so in integrated early stage database, we adopt timing update all.In the time that timing arrives, we all data update alls in original database to central database.Two, be that we only send to central database to realize synchronously by the incremental data that has occurred to change.Obviously, the second way is less to the pressure of the network bandwidth and server, and performance is far superior to first kind of way.So realizing between central database and each subdata base, the second way that in the model realization below, we adopt synchronizes.Utilize the increment information of database trigger database of record.Then complete the work such as transmission and data-switching of the amount of giving information, realize between central database and each subdata base and synchronizeing.Itself have stronger function for resembling the database such as Oracle, SQLServer, Mysql (Mysql 5.0 also provides trigger function), trigger function can be provided, we just adopt the renewal of the second incremental data.

Realize the asynchronous transmission of data security:

The accesses definition that Java messenger service (JMS) standard is messaging system the interface of one group of standard.WebLogicServer provides a kind of enterprise-level messaging system of supporting JMS API completely.This problem utilizes the JMS function in BEAWebLogic to realize the safe asynchronous transmission of message.In the point-to-point and distribution subscription model of two kinds of different Message-Passing Models of JMS, the safe and reliable transmission that JMS guarantees that by maintaining message queue or theme message is transmitted.

Feature:

(I) be the standard that cross-platform data represents and exchanges across, 1f platform: XML; JMS is based on Java language, thereby is also platform independence.JMS rain I XML has realized the behavior of platform independence and the data of platform independence together jointly.

(2) loose coupling: it is seamless between feasible system that each application system externally provides an interface based on XML data layout

Integrated.

(3) asynchronism: the application system of request msg does not need to be connected with the application system that sends data simultaneously.

(4) the asynchronous message mechanism of reliability: JMS the reliability of data transmission between application system.

(5) easily expansion: be all standard interface due to what use between system, so can increase with comparalive ease and reduce participation

Integrated subsystem.

Claims

1. the integrated method of the heterogeneous database based on XML and middleware is characterized in that subdata base system to change, and the trigger of establishment is recorded in the data that change in corresponding table.

2. client-side program timing arrives, and reads the table that record data change, and has data to exist, and extracts delta data, is converted into XML document.

3. XML document is converted to TextMessage, sends to] in the theme or queue of MS server.

4. the server end of monitoring this theme or queue receives this message, by corresponding crossover tool, the TextMessage message parse receiving is become to X letter document or DOM object.

5. the XML document obtaining is converted to the XML document corresponding to central data base system data by mapped file.

6. analyzing XML file, utilizes XML file data information updating central authorities shared data bank, finally realizes the integrated shared and synchronous refresh of heterogeneous database.