Heterogeneous database integration middleware based on Web services

1 background

Enterprises in the process of information left behind a large number of applications based on a variety of business processes and heterogeneous data sources of application systems. These systems meet a specific business needs of the enterprise, data has its own characteristics, other subsystems difficult to use the data of other subsystems, in the enterprise generated information "island" hindered the enterprise information process.

The integration of heterogeneous data sources in enterprises is an effective way to eliminate the "island of Information". This paper proposes a heterogeneous database integration middleware based on Web services to solve the following challenges in data integration:

1> heterogeneity: The biggest obstacle of multiple data source system is how to solve the heterogeneity of each data source. This heterogeneity is divided into platform heterogeneity, database system heterogeneity, semantic heterogeneity;

2> transparency: The greater the heterogeneity of the data source the higher the transparency requirement. Transparency mainly includes: platform transparency, data source transparency and semantic transparency;

3> self-control: Each local database has full control over itself, while being able to decide whether to provide and provide how much of its functionality and resources to serve other member systems.

This paper presents a solution of heterogeneous database integration middleware based on Web services for the above three problems.

2 Related Technology Introduction

2.1 Web Services

Web Services (Web Service) are initiated and defined by the World WIDE Web CONSORTIUM, and are now more popular as a software system that can be flagged with a URI, It uses XML-formatted information to define and describe external public interfaces and bindings. Web services can be discovered by other software systems and interact in a way that defines descriptions in a Web service by using xml-based messages with intelnet protocols.

Web services have the following characteristics:

1> Good encapsulation: For external users, he can and only see the list of features provided by the Web service object.

2> Loose coupling: Any changes that are implemented within a Web service are transparent to the external caller.

Standardization of 3> use protocols

4> highly integrated capabilities: Web Services completely mask the differences between different software platforms, and each platform can interoperate through standard protocols.

2.2 XML Technology

XML is developed by SGML (Standard generalized Markup, the standardized Universal Markup language), which defines the data structure in an open self-describing way, while describing the content of the data and highlighting the structure, thus reflecting the relationship between the figures. The main features of XML are as follows:

1> Scalability: Organizations, individuals can establish the appropriate set of requirements for their needs parameterization and semantic data.

2> structure: The data storage format is not restricted by the display format.

3> platform Independence: XML documents are plain text, independent of platform and application.

3 Integrated Middleware Solution

Middleware in the way of Web services to provide interaction, Web application clients and other application clients from different platforms, different software development environment to call the middleware Web services interface, so as to obtain data from different data sources, to achieve transparent access to data. The following is a detailed description of the core modules in the framework diagram of the middleware.

3.1 Core Module description

3.1.1 Middleware Configuration Module

1> Configure the current middleware and heterogeneous database connection information: Including database address, login username, password, database name. After this configuration is completed, the current middleware can use the local subquery module to obtain data from the configuration database.

2> configures current middleware and other middleware connection information: Includes user name and password for connecting to other middleware. This configuration enables the middleware to interconnect and form a data-sharing network.