On Mon, May 02, 2005 at 01:12:06PM -0400, Merlin Moncure wrote:
> I don't like the idea of listing user locks with 'tuple' locks for no
> other reason than this might confuse what user locks are. Even though
> they will be used as tuple locks 99% of the time, user locks are only
> loosely coupled with tuples in part because there is no sytem generated
> column which is persistent and > 32 bits. IMO, this is a problem with
> the current user lock module...it encourages locking over oid which is a
> bad practice.
Another way would be to allow user locks to use the four fields of
LOCKTAG. So the user would be able to establish more powerful
conventions: say the relation's Oid, and a related sequence value if
there is one; or a blocknumber/offset (ctid) if there isn't, etc.
> A properly implemented user lock system would likely
> maintain a global sequence shared by all lockable objects, tuple or
That'd just be equivalent to require that user tables are created WITH
OIDS, only the counter wouldn't be shared with system tables ... how is
that any better?
Alvaro Herrera (<alvherre[@]dcc.uchile.cl>)
"Ellos andaban todos desnudos como su madre los parió, y también las mujeres,
aunque no vi más que una, harto moza, y todos los que yo vi eran todos
mancebos, que ninguno vi de edad de más de XXX años" (Cristóbal Colón)