On Thu, 26 Jan 2006, Markus Schaber wrote:
> AFAIK, in PostgreSQL normal SQL commands cannot create deadlocks at all, > the only way to introduce deadlocks is to issue LOCK commands to take > locks manually. And for this rare case, PostgreSQL contains a deadlock > detection routine that will abort one of the insulting transactions, and > the others can proceed. That's not true. See all the complaints about pre-8.1 foreign keys and the row locks taken out by FOR UPDATE as an example. A simpler example than the one given before (with potential timing) is: create table t1 (a int); create table t2 (a int); insert into t1 values(1); insert into t2 values(1); T1: begin; T2: begin; T1: update t1 set a=3; T2: update t2 set a=3; T1: update t2 set a=2; T2: update t1 set a=2; ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
