Pamela AND brad,

>Uniqueness is enforced across deleted records also. The setting of SET DELETED ON doesn't make any difference. The reason for this is because a deleted record can always be RECALLed.

>This is another argument for "surrogate" keys.

This is incorrect. Surrogate keys do not have much to do with this problem. See Thread #434523 Message #491025 for an explanation of the problem and possible solution.

Walter,