* Pat Wibbeler <[EMAIL PROTECTED]> [2006-06-07 20:50]: > Beginning everything with BEGIN IMMEDIATE should eliminate the > possibility of deadlock, but you will serialize read-only > operations.
Why? BEGIN IMMEDIATE acquires a for-read lock. Multiple for-read locks can be acquired concurrently. It is only for-write locks that can only be acquired in the absence of any other locks, which leads to serialisation. Putting all your read operations in BEGIN IMMEDIATE means that all your write operations will be serialised in relation to all other operations taking place, but read operations can proceed apace. Of course, if your writes are short and frequent, they will likely take much longer than necessary if all your operations acquire read locks before they *really* need them. Regards, -- Aristotle Pagaltzis // <http://plasmasturm.org/>
