Show all storm names except for those with at least two affected regions.
create table storm (name varchar, PRIMARY KEY (name)); create table affected_region (storm_id varchar, PRIMARY KEY (storm_id)); create table storm (name varchar, storm_id varchar, PRIMARY KEY (name))
select name from storm except select t1.name from storm as t1 join affected_region as t2 on t1.storm_id = t2.storm_id group by t1.storm_id having count(*) >= 2