Table creating error

Question

Hi All.
I am working on an issue....there is one ztable named as zemp with the following fields:
MANDT     MANDT     CLNT     3     0     Client
ZNUM     ZNUM     CHAR     6     0     Employee number
ZDATE     ZDATE     DATS     8     0                                                                
ZROLE     ZROLE     CHAR     1     0     emp role
ZCLASS     ZCLASS     CHAR     2     0     emp class
where mandt is the only key field in it and now I am trying to put the data in it, when I put the first entry using sm30
1.
empnum             1
date               08/08/2008
zrole              3
empclass           12
and now when I am trying to enter the second record:
empnum          1
date            08/08/2008
zrole           2
empclass        12
it's giving me the following error:
An entry already exists with the same key
can you please tell me what exactly the problem is..
Thanks,
Rajeev

Answer 1

Thanks for the reply srinivas. This time I amde enum also as a key field and tries to enter the following records:
empnum             1234
date               08/08/2008
zrole              2
empclass           12
and now when I tried to enter the seod record as :
empnum          1234
date            08/08/2008
zrole           3
empclass        12
I am facing the same problem !!!