How to take a user table backup from that user account? I mean i want to give him grants to take backup... also query to take backup.

You need to run the EXP utility from the user account.

thank you debasisdas for posting, i already tried that, i m using java to take backup of oracle.... I want user to take backup remotely from any computer.. For exp he must have oracle installed.... Any idea?

1. create a backup script.
2. store it in the server.
3. call it remote when required.

It will be very kind if u post a sample script.... or just algorithm in post

Put this in a batch file and call as desired.

for /f "tokens=2,3,4 delims=/ " %%a in ('date /t') do set fdate=%%a%%b%%c
for /f "tokens=1,2,3,4,5 delims=: " %%a in ('time /t') do set ftime=%%a%%b%%c%%d%%e
exp userid=DEBASIS/DEBASIS@DEBASIS_DB file=C:\BACKUP\backup%fdate%%ftime%.dmp log=C:\BACKUP\backup%fdate%%ftime%.log
commented: Marvellous, Thanx +4