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1>
the primary key is (Car ID,Owner ID)
2>
Car ID,Owner ID -> {Owner Name,Make,Model,Year}
Car ID -> {Make,Model,Year}
Owner ID -> {Owner Name}
Model->{Year}
3>
The nomal form is relation in 1NF.Because firstly,this formal has a relation in which the intersection of each row and column contains one and only one value; Secondly,this formal have partial functional dependency on Car ID,Owner ID. so it is not a 2NF
4>
Apply normalization to it incrementally, bringing the relation to 2NF:
this relation that is in 1NF and have partial functional dependency on Car ID,Owner ID.
The formal of 2NF:
Car_Owner(Car ID,Owner ID)
Car(Car ID, Make,Model,Year)
Owner(Owner ID, Owner Name)
The Car:
Car ID -> {Make,Model,Year}
Model->{Year}
The Owner:
Owner ID -> {Owner Name}
After this change, this formal doesn't have partial dependency. Make,Model,Year only dependent on the primary key Car ID.Owner Name only dependent on the primary key Owner ID.
But this form have transitive dependency,This nomal form is 2NF,so we change from 2NF to 3NF.
The formal of 3NF:
Car_Owner(Car ID,Owner ID)
Car(Car ID, Make,Model)
the primary key is (Car ID,Owner ID)
2>
Car ID,Owner ID -> {Owner Name,Make,Model,Year}
Car ID -> {Make,Model,Year}
Owner ID -> {Owner Name}
Model->{Year}
3>
The nomal form is relation in 1NF.Because firstly,this formal has a relation in which the intersection of each row and column contains one and only one value; Secondly,this formal have partial functional dependency on Car ID,Owner ID. so it is not a 2NF
4>
Apply normalization to it incrementally, bringing the relation to 2NF:
this relation that is in 1NF and have partial functional dependency on Car ID,Owner ID.
The formal of 2NF:
Car_Owner(Car ID,Owner ID)
Car(Car ID, Make,Model,Year)
Owner(Owner ID, Owner Name)
The Car:
Car ID -> {Make,Model,Year}
Model->{Year}
The Owner:
Owner ID -> {Owner Name}
After this change, this formal doesn't have partial dependency. Make,Model,Year only dependent on the primary key Car ID.Owner Name only dependent on the primary key Owner ID.
But this form have transitive dependency,This nomal form is 2NF,so we change from 2NF to 3NF.
The formal of 3NF:
Car_Owner(Car ID,Owner ID)
Car(Car ID, Make,Model)
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cuiguoxin
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