Re: Humor me: Postgresql vs. MySql (esp. licensing) - Mailing list pgsql-general

From scott.marlowe
Subject Re: Humor me: Postgresql vs. MySql (esp. licensing)
Date
Msg-id Pine.LNX.4.33.0310101412540.19967-100000@css120.ihs.com
Whole thread Raw
In response to Re: Humor me: Postgresql vs. MySql (esp. licensing)  (Vivek Khera <khera@kcilink.com>)
List pgsql-general
On Fri, 10 Oct 2003, Vivek Khera wrote:

> >>>>> "sm" == scott marlowe <scott.marlowe> writes:
>
> >> will ungracefully kill the DB process(es).  Doesn't matter what DB (or
> >> any other application) you're running, you *can* lose data this way.
>
> sm> While it is possible to lose a non-committed transaction, WAL prevents the
> sm> database from becoming corrupted.  Assuming proper fsyncing of your hard
> sm> drives (i.e. SCSI, or IDE with write cache disabled)
>
> So you're saying it is not possible to corrupt the WAL if the process
> is ungracefully killed by the OS?

No, but it doesn't matter if it is corrupted, because the corrupted part
would be at the end, where a transaction was starting, and would just get
ignored.  i.e. postgresql would replay only the parts of the WAL that
were complete and showed as committed.


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