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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Primary Keys optional?
Well we do a lot of reporting on telco devices. Routers, servers, switches
etc. No pk or unique indexes. Just goes straight into various rollup tables.
The only uniqueness will be in the timestamps. So not much point. We also
keep track of customer orders for a service, say highspeed.The order doesn't
just come from one system but 4 or 5 systems each using a different customer
identifier. Hard to do pk-fk there and again you might only know the last
order because it's got the latest timestamp. However, we do create tables
with a single complete picture of orders which do have pk/fk constraints. I
do stress that the optimizer loves information and pk/unique indexes are
great info, but you can get alot of performance out of not null constraints
and indexes.
I would like to say that any user entry system we design is all pk/fk based
but that would be wishful thinking on my part.
Mike
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Aug 17 2006 - 12:16:36 CDT
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