Re: Oracle 8i and poor query performance in some queries

Niall Litchfield wrote:
> But if you are doing a FTS then the blocks go on the LRU list and get aged
> out rapidly. After all no-one in their right mind would scan the same blocks
> 35000 times when they could do it once now would they :(. It really seems
> like these tables get accessed frequently by the id column (and indeed there
> may even be RI between the columns) in which case indexing the id columns
> will probably cure this and other issues.

I admit that I'm not aware how Oracle's buffering mechanism ages out the blocks but it seems strange to me that the blocks are thrown out even when there is no need to free up buffer space for newer blocks. Why on earth blocks are thrown out or marked "no longer used" even when there are no data to replace them with? It would sound more logical to me to keep them there and also use them as long as there is no need to find room for some more important blocks. Well, I think I'll have to read and study the manuals.

-- 
Heikki