Re: Buffer busy wait clarification

"Chintu" <agarwalp_at_eeism.com> wrote in message news:1143116032.252091.53370_at_u72g2000cwu.googlegroups.com...
> Thanks a Lot Jonathan. You have made my day.
>
> But just 2 more questions. I hope I am not making you too angry.
>
> 1. When is the segment header first read in to the buffer.?? is when
> you query that table first time ??
>>>If the block does not have enough space (and usually it does,
> >> because that's why it is on the freelist at all), then the
> process
> >> may update the segment header to remove that block from the
> >> top of the list and replace -

    Yes.

> 2. What happens to the empty space which keeps a block in the freelist,
> but that space is not enough for the new row, and hence a new block is
> used. what happens to that block space ??. Will it be used for future
> updates ??
>

    The block goes off the freelist - so the space may end up being     wasted - but it is available for updates to other rows in the block.

> Thanks a TON Jonathan
>

-- 
Regards

Jonathan Lewis
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