What is a deadlock ? Explain .

Answer:

 

Two  processes wating to update the rows of a table which are locked by the other process then deadlock arises.

 

In  a  database  environment  this will often happen because of not issuing proper  row  lock  commands. Poor design of front-end application may cause this situation and the performance of server will reduce drastically.

 

These locks will be released automatically when a commit/rollback operation performed or any one of this processes being killed externally.