> > I don't understand what you mean by this. > > > > The primary purpose of adding row end time to primary key is to allow > duplicate value to be inserted into a table with keeping constraint in > current data but it can be duplicated in history data. Adding row > start time column to primary key will eliminate this uniqueness for > current data which is not correct
How? The primary/unique keys must always be unique at every point in time.
From user prospect it is acceptable to delete and reinsert a record with the same key value multiple time which means there will be multiple record with the same key value in a history data but there is only one values in current data as a table without system versioning do .I add row end time column to primary key to allow user supplied primary key values to be duplicated in history data which is acceptable
