Both primary key and unique enforce uniqueness of the column on which they are defined. But by default primary key creates a clustered index on the column, where are unique creates a nonclustered index by default. Another major difference is that, primary key doesn't allow NULLs, but unique key allows one NULL only.
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Option Strict On Public Module modMain Public Sub Main () Dim maxValue As Byte = &HFF Dim posValue As UIn...
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