If a table column has is UNIQUE and has NOT NULL, is it
equivalent to a PRIMARY KEY column?
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Answer Posted / sujith
no it is not.......... you may have some other columns which
have not null and unique constraints on it..... the thing is
that you should explicitly choose which one should be
treated as primary key so that clustered index can be put on
it, and non clustered on others where needed.........
foreign key may be used to refer to unique constraint
column, but while dropping you may loose relative unique
constraint also.. where as in case of primary referred by
foreign, will not allow so to happen............
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