Need help in IMP .dmp file

HI,

I tried to import .dmp file in oracle.i supplied the follwoing command :-

IMP ph1/ph1@test file=E:\test1.dmp full=y

i got the follwoing error : " Following statement failed because the object is already exist"

then i tried supplying the following command

IMP ph1/ph1@test file=E:\test1.dmp full=y ignore=y

i am getting this error :Row rejected due to oracle error1
encountered , unique constraint violated <id name>.

how can i proceed for the import.

expecting a valuable support on this.

Thanks.

imp
user/password@databasename
file=E:\test1.dmp
log = error.log
from =user
touser=user
grants=n
ignore=y

Are you appending to existing table?. ignore=y ignores only object existence, if you have data the constraint may be violated if you have a row with same values for constraint columns.

You can truncate the table and import again.