Show status

I'm not sure I understand the question entirely, but if you need to track when each row was added to the table, you can do that with a not-null datetime column that uses the GETDATE() function to set its default value.  This would do the job without any more work on your part.

There are two basic approaches to this. First one is to add column to the table indicating whether it was shown or not. Once it is shown, this field is updated and the row will not be shown again.

Second approach is to remember one field total, and that can be timestamp of last shown record (if table contains timestamp column), or identity of last shown record, etc. Somethign that would uniquely determine the last row shown. In that case, you show only those rows having this field larger than remembered value, and immediately you update that value.

Second approach is better if you have multiple users, so each user has seen different sets of rows.

Zoran