IBM Microsoft Oracle MySQL
Client/mobile DBMS with synchronization services X X X
Server DBMS X X X X
Extensive native XML support X X X
End-to-end database/application development tools X X X
Tight integration with Visual Studio X X
Tight integration with Eclipse X
Support for .NET Framework within DBMS X X
Support for Java virtual machine within DBMS X X
Windows support X X X X
Linux/Unix (AIX, HP UX, Solaris) support X X X
IBM zSeries and iSeries support X
Other operating system support (e.g., Mac OS) X X

Table 1 DBMS Competitive Features.
IBM, Microsoft, Oracle, and MySQL differ in some important respects.