When creating an index in Enterprise Manager, if you check create unique option, you are offered the option of 'Contraint' or 'Index'. Since 'Index' offers the option to ignore duplicate key it sounds a little like the 'unique' indexes in Fox: the index is unique but the table can hold duplicates; whereas 'contraint' seems to ask for true uniqueness. BOL is not very clear about the difference.

Can someone clarify, please? TIA.

Alex