On the pros and cons of object database and relational database

The object-oriented technology introduced in the late the 1960s caused a revolution. By the the 1980s, object-oriented technology has become the mainstream of the industry, for a variety of reasons: object-oriented not only simplifies the development of the interface, but also provides a more flexible, simple data processing methods, which fundamentally changed the way the application construction. Instead of using rigid two-dimensional tables to represent data like relational databases, object technology uses classes to describe the data. An object is an instance of a class, just like a particular oak tree is an example of an oak class.

Object technology uses inheritance schemes so that classes are designed hierarchically. The "oak" class can inherit data structure and data behavior from a more general class "tree".

Object technology can better describe the world we see, and object-oriented languages have proven to be more common in most programming areas. They make programming languages closer to mainstream ideas in natural languages and most software development areas. Object-oriented is a new paradigm and its impact will be long-lasting and far-reaching.

Object-oriented features are quickly added to a variety of mature languages, and thus some languages, such as C + +, have been achieved. A new object-oriented development environment has emerged, including Visual Basic,visual C++,powerbuilder,delphi, and Caché. Although object-oriented technology is widely supported in advanced development environments, it still takes a certain amount of time to form a formal curriculum. And it will take a long time to build a truly object-based world-a phase we have not yet reached.

The development of object technology on the World Wide Web

The Object-oriented programming language Java has become the favorite of Web developers as the World Wide Web transforms into a means of exchanging information. Based on C++,java can be used to create applets that can be executed in the browser (Java applets).

Sun provides a free Java environment to facilitate Java development. In just a few years, hundreds of thousands of Java environments are replicated and downloaded, and Java permeates every corner of the world. Java also raises more object-oriented languages, such as javascript,c# and JScript. The development of the Internet has also fostered some new object-oriented languages like Perl and PHP. Today's developers use object-oriented technology for granted.

The rise of the object

Object technology affects all aspects of software development. Object modeling has captured the market for application modeling, and the standard UML modeling approach is the top.

In the the 1990s, the appearance of object-oriented middleware products provided a secure communication service for object-oriented applications. The advent of JMS (Java messaging serivce) in 1998 made the middleware market a big step forward. JMS defines a set of messaging application programming interfaces (APIs) that enable certified Java EE applications to be introduced into a JMS server. This further strengthens the standardization process, greatly reduces the cost of the middleware, and provides an enterprise-wide object-based application platform.

XML and Web Services

In the 1998, HTML, an identity language dedicated to web design, has been further developed and standardized to create XML (an extended identity language). XML provides a complete set of syntax that can be used to create a custom data format that is similar to that stored in a database. With XML, programs can attach definitions to data and exchange data and data meanings. XML enables the definition of a specific standard data model, such as invoices or purchase orders, to exchange data between the company or the company. XML triggers the rise of Web services-programs that can interact with other programs immediately without requiring customer customization. There are now two types of Web service environments--j2ee and. NET. Like SQL, XML provides a standard for programmers to get data, but XML also provides a standard language for defining data at the object layer. XML grows as fast as object technology. As a result, new standards for data objects and new xml-based development products have emerged.

Object Database-A missing link

In contrast to the rapid application of object technology in every aspect of software development, object database is gradually accepted by people until now. There are many reasons for the slow action of object data.

The early object language did not consider data storage. The program works on the data, which is stored as a file, and the data is read as a file the next time the program runs. This approach makes it impossible to share data between applications, and data recovery, management, and expansion are almost impossible.

There are already a large number of object-oriented database products in the market: Versant,objectivity,objectstore,gemstone and so on. They provide the appropriate data storage for the object-oriented development environment. These products meet the initial enthusiasm, and even these products are expected to build a new database market--and may even become the market leader.

Unfortunately, relational database vendors have amassed tremendous momentum and captured a lot of market share when these object databases emerged. In a standard SQL interface, object-oriented programs that access relational databases are easy to write. In contrast, most early object data does not provide SQL interfaces at all, and is not suitable for any query application. As a result, object databases do not have a solid foundation in business. They have only created a small market in the application area to manage and store complex objects such as CAD/CAM, telecommunications, multimedia, artificial intelligence, analog financial equipment, patient diagnosis and tracking systems, and scientific applications.

The database market has never paid particular attention to object databases until the object definition language XML appears, which has facilitated the rendering of object databases again, since they are the most appropriate for managing XML-defined data. With XML, the need to store complex data is bound to increase, which will further trigger the recovery of object databases.

In September 03 InfoWorld published a developer survey, which had a surprising result, 89.2% of respondents said they used relational databases, and 52% of respondents said they used object-oriented or XML databases. When asked about the types of data stored, 40.2% said they store persistent objects, 58.9% said they store XML data, and 89% said they store relational data. Baroudi Bloor believes that object databases are more widely used than we think, and will further expand market share as demand surges.

InfoWorld's survey also shows that object-oriented language is the mainstream choice for new application development. We believe these statistics reflect the plight of developers today. They need a database that is better coordinated with the object-oriented language they have been using, but they need the query capabilities provided by relational databases.