database - SQL Query: ships with second biggest gun size -


i need query. problem have 2 schemas battleships , battles fought in: ships(name, yearlaunched, country, numguns, gunsize, displacement) battles(ship, battlename, result) question following: write query in battleships had guns second largest gun size. more precisely, find ships gun size exceeded 1 gun size, no matter how many other ships had larger gun size. list names of ships , gun size. attempted solve problem , answer following: 

select smax.name, smax.gunsize   ships smax ((select s.name,s.gunsize                 ships s                 s.gunsize not exists ( select ss.gunsize ships ss ss.gunsize >= all(select                  ss1.gunsize ships ss1))) temp)           , smax.gunsize >= (select temp.gunsize ships temp)

thank taking time read , answer !

try following:

select name, gunsize ships gunsize=(   select max(gunsize) secondbiggest ships    gunsize<(select max(gunsize) biggest ships)   )

edit: hint: secondbiggest , biggest aliases used clarifying each subquery does.


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