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I was reading some of the PAQ regarding Unique Constraint and Unique Index. I found this interesting post. Though, there are lots of things and I am confused. (<a href="https://www.experts-exchange.com/questions/22132268/Unique-Key-vs-Index-vs-Unique-Constraint.html" rel="ugc">https://www.experts-exchange.com/questions/22132268/Unique-Key-vs-Index-vs-Unique-Constraint.html</a>)<br />
<br />
Any way, <br />
My questions are:<br />
What is the difference between them?<br />
1) Syntax<br />
2) Logical Implementation<br />
3) Physical Storage
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I was reading some of the PAQ regarding Unique Constraint and Unique Index. I found this interesting post. Though, there are lots of things and I am confused. (http://www.experts-exchange.com/Microsoft/Development/MS-SQL-Server/Q_22132268.html)

Any way, 
My questions are:
What is the difference between them?
1) Syntax
2) Logical Implementation
3) Physical Storage

Unique Index and Unique Constraint

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