Re: Should I use PK or Unique Index in this table ?

In message <4159068a.423093_at_news.inet.tele.dk>, KennethKoenraadt@?.?.invalid writes
>On 27 Sep 2004 22:16:51 -0700, krislioe_at_gmail.com (xtanto) wrote:
>
>>Hi gurus,
>>
>>I have a employee table, when an employee firstly input into the
>>system, he/she does not have Emp_Number yet, after some approval
>>process only then Emp_Number is generated.
>>
>>Question is : since Emp_Number can be null at first, should I have PK
>>on this table ? or just Unique Index ?
>>
>>Thank you,
>>xtanto
>
>Hi Xtanto,
>
>Primary Key = Unique + Not Null ===>> Primary key constraint on
>Emp_number not possible.
>

But should probably use a sequence to give you a surrogate key and put a PK constraint on that as well.

-- 
Jim Smith
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