Re: does unique constraints hurt insert performance

<sunh11373_at_gmail.com> wrote in message
news:1155426742.867263.327670_at_p79g2000cwp.googlegroups.com...
> Hi,
>
> If I have a table which has 1 billion rows (data in each row is
> relatively small), delcare one column (not the primary key column) as
> unique, will this cause big problem for inserting?
> Assume the inserting rate is 500/sec and the possible duplication is
> 0.001%.
>
> Thanks
>

That's a question worth a bit of discussion, so I've put jotted down a few thoughts in a short article on my website.

    http://www.jlcomp.demon.co.uk/unique_constraint.html

-- 
Regards

Jonathan Lewis
http://www.oracle.com/technology/community/oracle_ace/ace1.html#lewis

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