Does the planner automatically add "limit 1" to "exists" sub-selects? In
other words, take an update like:
update foo
set itexists = exists
(select 1 from bar where bar.something = foo.something);
If the sub-select returns a large result set, will there be any benefit
to adding "limit 1" to the sub-select or does the query planner
automatically deduce that "limit 1" is the correct interpretation?
Cheers,
Steve