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Have some questions please answer its urgent:-
1. Describe where dbms is not better option & file base system is better.
2. How 2-phase locking differ from 2-phase commit.
3. Describe all ACID propertis?
4. Compare ms access and oracle?
5. What is fragmentation and its types?
6. How centralized dbms differ from distributed dbms?
In Oracle we are having variety of version Oracle 8, Oracle 9 etc what does the associated number means and same as Oracle 8i, Oracle 9i.
What does it means?
Acid properties: acid stands for
atomicity
consistency
isolation
durablity
atomicity modification on the data in the database either fail or succeed. The beginning of such a modification starts with a transaction and ends when a transaction finishes (either by a commit or a rollback). A software crash entails an implicit rollback.
Consistency only valid data (valid according to integrity constraints) may be commited.
Isolation one transaction does not interfere with another. The 'executor' of a transaction has the feeling that he has the entire database for himeself.
Durablity a commited transaction will not be lost. For two phase commit and two phase lock u refer
http:// user.it.uu.se / ~arnoldp / distrib / twophase . html
Your question is too much theoritical . It is beyond the scope of this discussions to explan all that here. You can easily find all that by little we searching.