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Home -> Community -> Usenet -> c.d.o.misc -> Re: PK vs Unique index
In article <m31ygqhxag.fsf_at_colorado.arsdigita.de>, Dirk says...
>
>> A primary key is much more then a unique index (doesn't even have to use a
>> unique index actually)...
>
>Could you explain this in a little more detail please?
Starting with 8.0 -- when we added deferrable constraints -- you can use a unique or non-unique index with a primary key.
If the constraint is deferrable -- a non-unique index must be used. If the constraint is non-deferrable -- either type may be used.
-- Thomas Kyte (tkyte@us.oracle.com) http://asktom.oracle.com/ Expert one on one Oracle, programming techniques and solutions for Oracle. http://www.amazon.com/exec/obidos/ASIN/1861004826/ Opinions are mine and do not necessarily reflect those of Oracle CorpReceived on Thu Jan 17 2002 - 07:00:34 CST