Question

Can you write below relations like these (with symbols)?

(∏ PName (σ TName = ‘Fire’ (Pokemon X Type))), (∏ SSN, Surname(σ Name = ‘Gary’ (Trainer)))

3)Select PName from Pokémon inner join InType on Pokémon.PID = InType.PID inner join Type on Type.TID = InType.TID where TName = 'Fire';

4)Select SSN, Surname from Trainer where name = 'Gary';

5)Select TName from Type inner join StrongAgainst on Type.TID = StringAgainst.TID_String where TID_Weak = 'Electricity';

6)Select Name, Surname from Trainer, Owns, Pokemon where Trainer.SSN = Owns.SSN and Owns.PID != Pokémon.PID ;

7)Select PName, TName from Pokémon inner join InType on Pokémon.PID = InType.PID inner join Type on Type.TID = InType.TID inner join Owns on Pokémon.PID = Owns .PID inner join Trainer on Owns.TID = Trainer.TID where Trainer.Name = 'Drizzt' or Trainer.Name = 'Bruenor';

8)Select PName, Name, Surname from Trainer inner join Owns on Owns.TID = Trainer.TID inner join Pokémon on Pokémon.PID = Owns .PID group by PName having count(PName) >= 1;

9)Select Trainer.SSN from Trainer, Owns, Pokémon, SpecializedIn where Trainer.SSN = Owns.SSN and Owns.PID != Pokémon.PID and Trainer.SSN = SpecializedIn.SSN;

10)Select Nickname from Pokémon inner join Owns on Pokémon.PID = Owns .PID where weight = (Select max(weight) from Owns);

11)Select PName,Weight,Height from Pokémon inner join Owns on Pokémon.PID = Owns .PID inner join Trainer on Owns.TID = Trainer.TID where Trainer.SSN = '1837837';

12)Select PName, Level from Pokémon inner join Owns on Pokémon.PID = Owns .PID inner join Trainer on Owns.TID = Trainer.TID inner join SpecializedIn on Trainer.SSN = SpecializedIn.SSN inner join StrongAgainst on SpecializedIn.TID = StrongAgainst.TID_Strong where TID_Weak = 'Rock' or TID_Weak= 'Water';

Answer 1

Note: As Chegg’s Policy I’m only allowed to answer the first 4 parts of a question. Please post the other questions separately.

3) Select PName from Pokémon inner join InType on Pokémon.PID = InType.PID inner join Type on Type.TID = InType.TID where TName = 'Fire';

Π_Pname (Pokemon ⋈_{(Pokemon.PID=InType.PID)} InType⋈_{(InType.TID=Type.TID ⋀ TName=’Fire’)} Type)

4) Select SSN, Surname from Trainer where name = 'Gary';

Π_{SSN, Surname} (σ_{(name=’Gary’)} (Trainer))

5) Select TName from Type inner join StrongAgainst on Type.TID = StringAgainst.TID_String where TID_Weak = 'Electricity';

Π_Tname (Type⋈_{(Type.TID=StrongAgainst.TID_String ⋀ TID_Weak=’Electricity’)} StrongAgainst)

6) Select Name, Surname from Trainer, Owns, Pokemon where Trainer.SSN = Owns.SSN and Owns.PID != Pokémon.PID ;

Π_{Name, Surname} (σ_{(Tainer.SSN=Owns.SSN ⋀ Owns.PID!=Pokemon.PID)} (Trainer X Owns X Pokemon)