This enables the developers to centralize application logic in the database. Oracle provides powerful functions and sub-queries in its SQL statements. Developers can distribute systems by database links, materialized views and distributed queries. This feature saves much cost for developing distributed systems and applications. And there's a lot of features integrated with Oracle, compare to other database it is very expensive but it is extremely powerful and fast. DB2 is a relational database system developed by IBM Corporation. It has been designed for use on large mainframe computer systems running on a variety of platforms including SunOS, Solaris, Linux, Windows 95/98/NT/2000 and HP-UX. DB2 supports many variety of platforms, standards and packaging options to deliver the needs of every business DB2 database delivers a flexible and cost-effective database platforms achieving demand on business applications. It further leverages the resources with broad support for open standard and popular development platforms include J2EE and Microsoft.NET. The primary internal database scripting language for DB2 are SQL/PL, Java and C. SQL/PL is compiled which means it performs better whereas Oracle's PL/SQL is interpreted. In terms of command, DB2 is much simpler to create, monitor, backup and restore database. It is portable database because DB2 exist everything from PDA through PC, midrange server, a cluster up to mainframe. According to an Online article on DB2 v Oracle Quick Comparison Guide,

DB2's optimiser is considered better than Oracle in deducing the most efficient access plan. Oracle allows you to overrule the optimiser by using hints, however, whereas, DB2 does not have this. The disadvantage of relying on hints is that they only produce the most effective access plan for a known volume of data. DB2's total cost of ownership is much lower than Oracle. The reason for this is that IBM don't bundle in additional, little used, functionality in to their main product and charge you...

Industry-leaders including like the Associated Press, Google, NASA, Sabre Holdings and Suzuki uses MySQL because it is an alternative to higher-cost and more complicated database technology. Its features include speed, scalability, reliability, easy to use and deploy and cross-platform support. It is available on more than twenty different platforms; this includes UNIX, Linux Distributions, Mac OS X, and Microsoft Windows. The difference of MySQL to other Database Management System is that it has a very limited support for sub-queries and other advanced techniques. This is not very much acceptable at a large company. The additional cost for the developer's time to work around on the database limitations cost far more at a large company that the database software itself. MySQL and Access will very much suited to perform well for the common small business applications which will not be suited when needed by a worldwide system for a fortune 100 company.
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