Re: buffer hit cache ratio

> that is not accurate. milsap is active on oracle-l_at_fatcity.com. He has
> repeatedly said that BHCR is only useful to tell you if you have alot
> of very bad sql. Namely if its VERY high, you have alot of terrible
> sql.

I'm not even sure that one can accurately make that claim for *every* case. Like most things, it all depends... What if you have a very small database and the data that gets accessed never gets aged out of the cache, and yet the SQL statements do not perform a lot of logical I/O? Does this mean that your SQL statements are terrible? You may have very good SQL statements. I agree that this is an extreme case that is very rarely seen in practice, but it is possible.

Cheers,
Brian

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