SELECT TYPE FROM ship WHERE flag  =  'Panama' INTERSECT SELECT TYPE FROM ship WHERE flag  =  'Malta'
What types of ships have both ships that have Panama Flags and Malta flags?
SELECT TYPE FROM ship WHERE flag = 'Panama ' INTERSECT SELECT TYPE FROM ship WHERE flag = 'Malta '
select type from ship where flag = value intersect select type from ship where flag = value
What types of ships have both ships that have Panama Flags and Malta flags ?