Re: Linking data together

[Peter Brawley]

> A TRIGGER could change one row when you UPDATE another.

Won't work:

drop table t;
create table t(i int,j int);
insert into t values(1,1),(3,3);
create trigger updt before update on t for each row update t set j=j+1 where i=old.i+1;
update t set j=j+1 where i=1;
ERROR 1442 (HY000): Can't update table 't' in stored function/trigger because it
is already used by statement which invoked this stored function/trigger.