Identity without Primary Key or with....which is the difference

Guys, one question: which is the main difference between using Identity and using either Identity and Primary_Key? It looks a stupid question (and maybe it is) but...maybe is not so stupid.

Primary Key is a logical implemention which creates behind the scene unique clustered index (physical implementation)
BTW, if you use an INDENTITY property and do not have PK on this you may end up with duplicates , ans also someone my reseed the values...
Best Regards,Uri Dimant SQL Server MVP,
http://sqlblog.com/blogs/uri_dimant/
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Large scale of database and data cleansing
Remote DBA Services:
Improves MS SQL Database Performance
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Using identity you may end up with duplicates??!!

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Name                                                  Null?    Type
M_ROW$$                                                        VARCHAR2(255)
SNAPTIME$$                                                     DATE
DMLTYPE$$                                                      VARCHAR2(1)
OLD_NEW$$                                                      VARCHAR2(1)
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Hello,
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saket bansal wrote:
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In the case without primary key

Hi experts,
In the case without primary key, we can define a primary key?
In the case
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Edited by: 891982 on 21 ก.ค. 2555, 18:41 น.

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Refer to http://e-docs.bea.com/wls/docs81/faq/ejb.html/#257430
"Jingwei Zhang" <[email protected]> wrote:
>
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Identity without Primary Key or with....which is the difference

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