ORACLE® Database

Oracle Database is the first database designed for enterprise grid computing, the most flexible and cost effective way to manage information and applications

Overview of Scalability & Performance Features

Oracle resolves issues by using various types of locks and a multiversion consistency model. These features are based on the concept of a      

    transaction

The simplest way to think of Oracle's implementation of read consistency is to imagine each user operating a private copy of the database, hence    

    the multiversion consisten-

             cy model

Oracle also uses locks to control concurrent access to data. When updating information, the data server holds that information with a lock until the update is

     submitted or committed

One way to provide  from concurrent non-database administrator isolation is to shut down the database and reopen it in restricted mode. You could also put the system into quiesced state without disrupting users

RAC comprises several Oracle instances running on multiple clustered computers, which communicate with each other by means of a so-called interconnect

Oracle provides unique portability across all major platforms and ensures that your applications run without modification after changing platforms