"Mladen Gogala" <gogala_at_sbcglobal.net> wrote in message
news:pan.2006.03.12.03.00.10.479507_at_sbcglobal.net...
>
> The "indexed FK" lore applies only to OLTP databases. The common wisdom,
> which I subscribe to, is always to index foreign keys. Yes, you might be
> wasting some resources, but if you don't do that, you are risking
> deadlocks and a serious downtime. I will gladly waste some resources to
> prevent that from happening, even if it means few MB and CPU cycles
> wasted. There is so called 80:20 law which says that in order to achieve
> 80% improvement, you need 20% of the effort needed for 100% improvement.
> The corollary is that for remaining 20% one needs 80% of the effort. I
> have better things to do then to worry about deadlocks, if I can prevent
> them. Even if the table is not a significant risk today, nobody guarantees
> that the purpose of the table will not be changed tomorrow.
>
> --
The 80-20 rule that I subscribe to says that 80% of DBA's are not smart
enough to figure out when an index is needed and when it is not. Probably
the real ratio is 95-5.
Received on Sat Mar 11 2006 - 21:09:37 CST
