A risk you're willing to assume.

I am always willing to assume I am stupid. :)

First of all, frequently used tables live in the cache, so nothing
is going to improve their access times.

I guess this is true if your cache is big enough.

User level tuning is the first resort of incompetents.  The database
knows what it's doing, you don't.  Expecting a human to tell a computer
how it should run its affairs is just plain dumb.

I guess I am not used to this way of thinking from software manufacturers especially database manufacturers. When you look at the hundreds of tuning tweaks one can make to oracle you'll see what I mean.  I tend to agree with you that the software should know best how to tune itself and that you shouldn't need a highly paid DBA to constantly tweak it nor a week to install it. Having said that though I also think you should be able to override the default tuning if you think your particular set of data is unique enough to warrant it.

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             Tim Uckun

      Mobile Intelligence Unit.

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   "There are some who call me TIM?"

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