SELECT cName FROM  tryout WHERE pPos  =  'mid' EXCEPT SELECT cName FROM  tryout WHERE pPos  =  'goalie'
Find the names of schools that have some players in the mid position but not in the goalie position.
[Schema (values) (types)]: | soccer_2 |  College : cname (text) , state (text) , enr (text) | Player : pid (text) , pname (text) , ycard (text) , hs (number) | Tryout : pid (text) , cname (text) , ppos (text) , decision (number);