IBM and DB2 9 open a new era of hybrid database management systems

New troubles brought by new technologies
XMLExtensible Markup Language) technology is a self-describing data structure with great flexibility. It is recognized by all parties for its scalability, platform independence, and ease of exchange. With the evolution of business and IT technology, more and more companies have begun to widely adopt XML technology. At the same time, in order to exchange data between different systems and applications to adapt to rapid changes in the business environment, a large number of enterprises began to establish SOAService Oriented Architecture and service-Oriented Architecture ), XML is the foundation of SOA. Therefore, almost all famous IT enterprises are looking for ways to efficiently share, search, and manage a large number of XML documents and messages produced by the company, this helps companies reduce the time and effort required to store and use XML data, thereby reducing development costs and improving business flexibility.

To manage new data forms, enterprises often have to face new challenges. The rapid growth of XML format data has brought such troubles to enterprises. The XML data model differs greatly from the traditional relational model. The relational model is based on Relational (table) and attribute (column, the XML data model is based on the relationship between nodes (elements, attributes, notes, and so on) and nodes, at present, common methods for managing and sharing XML data have certain defects.

File systems can handle simple tasks, but they are vulnerable when a large number of documents need to be processed, making it difficult to manage concurrency, recovery, security, and availability issues. Commercial relational database management system (DBMS) solves these problems, but it is still lacking in other aspects, they often provide two basic database design options-to completely store Each XML document as a large object, or to split it up and store it in multiple columns of multiple tables, in many cases, these options may cause performance problems, difficult management, increased query complexity, and other problems. Pure xml dbms introduces a new type of environment in IT infrastructure, and this environment has not been tested yet, its integration capabilities, required personnel skills, and future vitality are still unknown, which may cause many risk factors.

So how can we make full use of all the features of XML and store XML data in a simple and efficient manner?
IBM DB2 9
In the face of these challenges, after years of accumulation and continuous innovation, IBM was the first in the industry to launch the first hybrid data server that directly supports XML-IBM DB2 9 codenamed Viper ).

IBM DB2 9 provides a very different architecture from previous versions, it provides new query languages, new storage technologies, new indexing technologies, and supports the features of XML data and its inherent hierarchies, makes IBM DB2 9 the first "hybrid" (Multi-structure) Database Management System of IBM. In addition to table data models, DB2 also supports hierarchical data models inherent in XML documents and messages. Users can freely store traditional SQL data and the latest XML data in a table. You can also query and process data in these two forms by using SQL, XML extension, and XML Data Query standard emerging in XQuery. Extended on proven database management infrastructure, IBM provides DB2 9 users with powerful support for simultaneously processing relational and XML data. New XML-based applications use DB2 to seamlessly access relational database resources and have the ability to access enterprise-level XML applications.

DB2 integrates support for XML data in all features/interfaces, while DB2's "inherent" Support for XML is provided out of the existing support for other technologies, SQL, table data structures, and various DBMS features are currently the best supported. Therefore, you can use a database object to manage "traditional" SQL data and XML documents at the same time.

To efficiently manage traditional SQL data types and XML data, DB2 has two different storage mechanisms. However, you must note that the underlying storage mechanism used for a given data type is transparent to applications. In other words, applications do not need to explicitly specify the storage mechanism to be used or manage the physical details of storage. For example, how to split each part of an XML document into multiple database pages. The system automatically uses the appropriate format for the target data, and the application naturally obtains runtime performance advantages in data storage and query.
Unique Feature of DB2 9
DB2 enables users to fully store XML documents, while DBMS fully master the internal structure of documents. This avoids or reduces the management tasks and programming tasks involved in other solutions. In addition, it can accelerate searches between documents and within documents, so that customers can quickly adapt to the changes in business requirements reflected in the XML mode. DB2's only requirement for storing XML data is that it must be a well-formed data. That is to say, it must comply with the syntax rules specified in the W3C XML standard. This loose method provides users with great flexibility and makes it easier to store XML document sets containing different attributes and internal structures.

The XML document set is stored in DB2 tables. These tables contain one or more columns of the New XML data type. To make it easy for users to integrate traditional forms of business data and XML data, DB2 administrators can create tables that contain both traditional SQL data type columns and New XML data type columns. This allows administrators to use familiar SQL data definition language DDL statements to create database objects for storing XML data. But in fact, this familiar interface hides the fact that DB2 stores XML data in different ways. It uses new technologies to store XML data hierarchies, it also supports efficient searching for all parts of the original XML data. DB2 uses a parsed format to store and operate XML data. This format can reflect the level of the original XML document. Therefore, it uses trees and nodes as models to store and process XML data. If you require DB2 to test the XML data for the registered XML mode before storage, DB2 will mark all nodes in the XML hierarchy with the schema type information; otherwise, label the node with the default type information.

DB2's New XML support includes the new query language function. Programmers can now use SQL or XQuery to search for data. XQuery is a new query language that supports path-based expressions for navigation. In fact, applications can freely use the statements in these two languages, and a query statement can be combined with SQL and XQuery.

New features supported by DB2 for XML include extensions to familiar management tools, which can help administrators manage and adjust databases. For example, backup and recovery facilities, including high-availability data replication for fault recovery, support documents stored in XML columns. DB2's graphical management tool DB2 Control Center enables administrators to browse tables containing XML data, create and manage XML-based indexes, issue SQL/XML and XQuery statements, and execute many other management tasks. Because performance is often the focus of attention, the corresponding DB2 facilities are also extended to adapt to XML data. These facilities include DB2 Snapshot Monitor ("Snapshot"), which provides a summary of DB2 activities at a certain time point; RUNSTATS, which collects statistics on data stored in the DB2 database; and EXPLAIN, it reports that the query optimizer is the access path that meets the specified request. The administrator can determine which XML indexes are used by studying the EXPLAIN output.

If programmers cannot reliably access the XML data stored in the database, the New XML support of DB2 is meaningless. With this recognition, IBM has enhanced its various programming language interfaces to support easy access to XML data. These enhancements cover Java? JDBC), C embedded SQL and calling interfaces), COBOL embedded SQL), PHP and Microsoft? . NET environment through the DB2.NET data provider ).

DB2 9 is the first database that supports both relational data and built-in XML data. It perfectly integrates XML with traditional relational databases, it enables users to obtain the most advanced technical features and superior performance at the minimum cost. It opens a new era of hybrid database management systems and is an epoch technological innovation of IBM in information management over the past 26 years, leading the new peak of data management will surely become a new milestone in the history of database development.