Subject Re: [IB-Architect] Disk data integrity (was: Torn Page detection)
Author Ann Harrison
>Claudio wrote:
> >
> > For what I understand, the engine only ensures the TIP is written
> after the
> > page itself has been written (so there may be orphan pages but not dangling
> > references to non-extant pages).

At 06:28 PM 11/14/2000 +0100, Ivan Prenosil wrote:

>I believe that it is more complex than just deferring writing of TIP.
>Everytime IB needs to write page that contains pointer to another page,
>it must choose right order of write operations.

That's correct. The data structures in InterBase are designed not
to include loops (pages that point to each other) and are written in
such an order that the database on disk is always correct.

If forced writes are used, even if the server crashes the database
on disk will never contain a pointer into oblivion.