Oracle is very fast and powerful but requires significant expertise to maintain. MS SQL is easier to install and administer but is not not as "scalable" as Oracle. Although you can "cluster" several computers together to improve SQL Server's performance, with Oracle you can use a grid of hundreds of computers to give your database virtually unlimited performance.
Difference are:
1. Oracle more complex consider as MS sql DataBase.
2. Oracle compatible to all operating system platform but MS sql compatible only windows and Linux operating system.
3. In Oracle in transaction control all task consider as one unit but in other MS sql to treat as a individual commands so take more time consumption in sql compare to oracle.
4. In MS Sql all database is private so no share to other disk on other side in oracle the object of database are shareable so increase the availability in other remote site cause of most useful for distributed operating system.
5 In the term of functionality MS sql not permitted to partitioning , reverse key indexing and bit map index but in Oracle all functionality are permitted so along with this to enhance the flexibility.
Now to gain more knowledge visit at:
Oracle is very fast and powerful but requires significant expertise to maintain. MS SQL is easier to install and administer but is not not as "scalable" as Oracle. Sql provide more functionality,provide separate query analyzer and enterprise manager,oracle data base more secure