Every database vendor says, their database is the best. Today’s highly dynamic and competitive business environment puts pressure, to sell more application and services at a reasonably low cost. At the same time for a solution provider, it is not possible to have database neutral system, since there are no established standards across database systems. To capitalize market, every vendor must have some uniqueness, which make the database ‘better’ than its competitor!.

Hence the best approach is to have the system, make to run under various databases (provided there is revenue stream), utilizing the best of the underlying databases.

It is not true that Oracle Database is better than DB2 or MY Sql or vice versa. These products can be used to build stable and efficient systems and the stability and effectiveness of the applications depends, rather from the experience of the database developers (to exploit and use the power of the DB) and database administrator than from the database's provider.

MY Sql, DB2 and Oracle separate the client code and the server code in different address spaces. The application code runs in the client process while the server code runs on separate processes. The client processes can run on the same or different machine from the database server, accessing the database server via a programming interface. My SQL, DB2 and Oracle support dynamic and embedded static SQL interfaces among others such as Sybase and SQL server.

Oracle PL/SQL is a programming extension of the standard SQL. All Oracle stored procedures, user-defined functions, and triggers must be written in PL/SQL. Instead DB2, users can use any programming languages supported by the pre-compiler such as C, C++, Java, Cobol etc. to construct the DB2 stored procedures. SQL Plus provides Oracle command line access to the database server. DB2 has a similar tool called the Command Line Processor (CLP). However, CLP does not have all of the features of SQL Plus (such as spooling). Instead IBM recommends, to use the Control Center Script Center to perform some of the scripting and scheduling activities.

DB2 does not require a contiguous set of data blocks to store data as in Oracle. Hence, there is no fragmentation problem in DB2 tablespaces. This is a real advantage. The price comparison is also important, since Db2 is much cheaper in terms on price per seat and server sizing.

The most important feature being, while selecting / converting to any Database, the application must use the power of the underlying database. Hence if any application is written / migrated (for Data access), then the application should use the power of the database. This is where the system architecture, design and application partitioning comes very important.