Re: timeout on lock feature

> Timeouts are a system-level mechanism that to be useful must refer to
> system-level events that are far above anything that PG knows about.
> The only way PG could apply reasonable timeouts would be for the
> application to dictate them, but the application can better implement
> them itself.

OK we have the following scenario

Session A Session B

begin begin

insert -- on unique constraint

insert -- on same unique constraint

-- Session A becomes idle

: -- Session B becomes ...

or we have (Informix Online)

Session A Session B

set lock mode to wait [seconds] set lock mode to wait [seconds]

begin begin

insert -- on unique constraint

insert -- on same unique constraint

* resource not available error *

-- Session B carries on

Oracle 7 (OCI) has oopt() call to set wait options for requested
resources. Oracle 8 OCI has the same behaviour as PG ie. oopt()
is no longer available.

I believe that the ability to switch the database to either not wait
for resources, or wait a specified period or wait forever
(default) is essential especially for interactive applications.

Regards
Theo