TYPO3 Core

+1
this can also be useful if someone edit a record, it can be locked for other users.

I attached an intial version (experimental and not much tested).
Since the patch extends the TYPO3_DB object, also DBAL should be envolved in using these locks. A "typo3_dbLock" package for Oracle is attached (thanks a lot to "Sigi").

MySQL's GET_LOCK() is a no-go. The following "locking" in one process will release the first lock:
SELECT GET_LOCK('lock1', 10);
SELECT GET_LOOK('lock2', 20); --> releases 'lock1'

The new patch creates a sys_lock table which holds these locks.
When the database hammers/polls if a lock is active, the information will come from the database cache until the lock is released or changed.

I see no other possibility to implement such a lock for a concurrent scenario.

Sounds great, Olly. Any way to test or use this kind of locking?

Currently I only see the page generation using t3lib_lock in the core. It's type can be set using ['SYS']['lockingMode'], which defaults to 'simple'.

Maybe we can introduce the new DB based locking to the core and test it using that lock? And later on we can make use of it for other situations.

related to: http://bugs.typo3.org/view.php?id=16749

I'm unsure if we really need an own table for this. Probably the registry could be used for this, too.

I agree, this is a perfect job for the registry...