Re: partitioning and locking problems

On Thu, 2006-02-02 at 11:27 -0500, Marc Morin wrote:

> > > 1- long running report is running on view
> > > 2- continuous inserters into view into a table via a rule
> > > 3- truncate or rule change occurs, taking an exclusive lock.
> > > Must wait for #1 to finish.
> > > 4- new reports and inserters must now wait for #3.
> > > 5- now everyone is waiting for a single query in #1. Results
> > > in loss of insert data granularity (important for our application).

> Using a separate lock table is what we've decided to do in this
> particular case to serialize #1 and #3. Inserters don't take this lock
> and as such will not be stalled.

Would it not be simpler to have the Inserters change from one table to
another either upon command, on a fixed timing cycle or even better
based upon one of the inserted values (Logdate?) (or all 3?). (Requires
changes in the application layer: 3GL or db functions).

The truncates can wait until the data has stopped being used.

I'd be disinclined to using the locking system as a scheduling tool.

Best Regards, Simon Riggs