Your independent resource on business integration and network computing through middleware and message brokering

Data Access Middleware:
Seeking Out The Middle Ground

Charles J. Bontempo and C. M. Saracco
IBM Corporation

	This is an abstract of an analysis that was first published in   MIDDLEWARESPECTRA. You can order a complete version of this analysis on line by clicking the order button above.

Management introduction

The evolution of database access middleware proceeds apace and is taking many different product and approach paths. From the initial delivery of 'simple' database access tools often accessing a minimum of data stores and specialized for individual databases there is increasing attention being paid to more general middleware tools. Data warehousing is an active pressure in this field.

In this analysis, two IBMers Mr. Bontempo, a database consultant, and Mr. Saracco, author of Database Management: Principles and Products (Prentice Hall) examine the evolution of data access middleware and use the DataJoiner product to illustrate what they think users should look for. In addition, Colin White President of DataBase Associates International and of InfoDB (by whose permission this analysis appears) discusses:

• additional, similar, implementations (from HP, IBI and Sybase)
• what to look out for when comparing possible candidate products.

Figure 23: Data access middleware architecture
Figure 24: Using dataJoiner to join DB2 and Oracle
Figure 25: The HP, IBI and Sybase hub servers as middleware (by Colin White)

Management conclusion

A true multi-database server can provide one component of a data warehouse when it is supplemented by appropriate tools for cleansing, transforming, and integrating data prior to storing it in a warehouse database. The warehouse database might function as another data source for the data access middleware.

Or, if the multi-database server includes its own full function DBMS, the warehouse data can be managed as a local database by the multi-database server. In this way client requests for warehouse data can be handled more directly, since they can be satisfied by the server without access to a remote data source. This is the role for data access middleware.

	This is an abstract of an analysis that was first published in   MIDDLEWARESPECTRA. You can order a complete version of this analysis on line by clicking the order button above.