> It's not a full solution anyway since it prevents any kind of update
on the table due to check constraints firing even if target field not
updated. >
Well, we can extend the check within the trigger:
if (coalesce old.a=new.a -- Update
OR
new.a = currval(tg_argv[0] -- Insert
) then
return new;
end if;
Marc
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
