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Unique Index vs. Unique Constraint

P: n/a
Does a Unique Constraint build a unique index?

What is the difference?

Thanks,
Thomas LeBlanc

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Nov 12 '05 #1
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3 Replies


P: n/a
On Fri, 10 Oct 2003 13:59:38 -0500, "Thomas LeBlanc"
<th*********@hotmail.com> wrote:
Does a Unique Constraint build a unique index?
Yes.
What is the difference?


A constraint is an abstract concept, an index is an implementation
detail.

Servus
Manfred

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Nov 12 '05 #2

P: n/a
On Fri, 10 Oct 2003, Thomas LeBlanc wrote:
Does a Unique Constraint build a unique index?

What is the difference?


None that I know of.
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Nov 12 '05 #3

P: n/a
scott.marlowe wrote:
On Fri, 10 Oct 2003, Thomas LeBlanc wrote:
Does a Unique Constraint build a unique index?

What is the difference?


None that I know of.


A different implementation of UNIQUE constraint might allow
deferrability, what our index solution does not ... yet.
Jan

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Nov 12 '05 #4

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