This is getting way off topic, but:
On 5/11/10 3:55 PM +0300, Nicolas Barbier wrote:
> T2> SELECT i FROM a WHERE i = 1 FOR SHARE; -- Lock a with i = 1 FOR SHARE.
> i
> ---
> 1
> (1 Zeile)
>
> T2> SELECT a_id FROM b WHERE a_id = 1; -- Check whether it's got
> anything pointing to it.
> a_id
> ------
> (0 Zeilen)
>
> T2> DELETE FROM a WHERE i = 1; -- Nope, so delete a with i = 1 (this
> blocks, because T1 is still holding the lock).
Obviously you wouldn't delete anything with a SHARE lock.
Regards,
Marko Tiikkaja