Chris Bowlby <[EMAIL PROTECTED]> writes: > I've been working on a small module that I will be pluging into my > local PostreSQL 8.x database and am in need of doing some table locking. > At this time, I've used various other examples to no avail and was > wondering what the proper method for aquiring a table lock within the > module would be?
You should not be touching locks at any level lower than lmgr.c's exports; eg LockRelation() not LockAcquire(). The LockAcquire API is not as stable. Usually people take a relation lock in combination with opening the rel in the first place, ie, specify the desired lock to heap_open or relation_open or one of their variants. If you apply LockRelation() to an already-opened rel then you need to be worrying about possible deadlocks due to lock upgrading. Also, 90% of the time you probably don't want to release the lock explicitly at all; leave it to be held until transaction end. Early release violates the 2PL principle, so you need to analyze things pretty carefully to determine if it's safe. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org