please answer my questions

[salohi]

1.what are the disadvantages of file system and how does DBMS overcome them?
2. explain the locking protocols used in concurrent access management?
3. what is WAL,and why is used?
thanks for any ony try to answer these questions...... .......

[MMcCarthy]

Salohi

If you give a more descriptive answer to your question in future it would help to attract the appropriate experts to you post.

1.what are the disadvantages of file system and how does DBMS overcome them?
2. explain the locking protocols used in concurrent access management?
3. what is WAL,and why is used?
thanks for any ony try to answer these questions...... .......

[salohi]

ok
can i know, why WAL is used for?