Re: WaitOnLock error - what does this mean?

On Sun, 23 Jul 2000, Tom Lane wrote:
> "Robert B. Easter" <reaster@comptechnews.com> writes:
> > ERROR: WaitOnLock: error on wakeup - Aborting this transaction
>
> Is there any NOTICE coming out right before that?

Yes.  After sending my email to this list, I kept trying the same thing again.
After a few more tries, my php script managed to do an insert but when I
looked at the inserts running from bash I saw both the NOTICE and ERROR.  My php
script only reports ERRORs when a query fails (not sure if php has any ability
to report notices). Its random which inserts will be the cause of deadlock. I
guess I'll just have to make the script output a more user-friendly message
like: system is too busy, please try again later.  Is my database design flawed
if this occurs?

>
> For example:
>
> psql #1:
>
> begin;
> lock table tenk1;
>
> psql #2:
>
> begin;
> lock table tenk2;
> lock table tenk1;
>
> <waits>
>
> psql #1:
>
> lock table tenk2;
>
> NOTICE:  Deadlock detected -- See the lock(l) manual page for a possible cause.
> ERROR:  WaitOnLock: error on wakeup - Aborting this transaction
>
>
> Not sure why this isn't just one ERROR, since anyone using a client that
> discards NOTICEs is going to be confused...
>