Re: foundations of relational theory? - some references for the truly starving

In article <B6nmb.22188$e01.46207_at_attbi_s02>, Marshall Spight <mspight_at_dnai.com> writes
>"Mike Preece" <michael_at_preece.net> wrote in message news:1b0b566c.0310240556.3bf
>271e6_at_posting.google.com...
>> >
>> > BS. Or do you mean you don't write to log files ?
>>
>> No - we don't usually. It's not usually wanted or needed. We can if
>> you want. It's very easily done - centrally, with a trigger fired when
>> the file is updated if you'd like.
>
>So, what happens if you have a power failure or an OS or application
>crash when you've written the first page of a two-page update?
>Does Pick have transactions?

Yes.

If you're interested in the details, it probably flushes the pages to disk, NOT overwriting the originals, and then updates the pointers to point at the new pages not the old ones. That makes sense to me, and I know that trick is used by some journalled file systems.

Cheers,
Wol

-- 
Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
Witches are curious by definition and inquisitive by nature. She moved in. "Let 
me through. I'm a nosey person.", she said, employing both elbows.
Maskerade : (c) 1995 Terry Pratchett