4.3 Further normalisation

Supp-part(sno,partno,partdesc)
Cust-supp(partno,custid,,sno,custname,custaddr,quantity)

  sno -> sname,saddr
  partno -> partdesc
  partno,custid,sno -> quantity
  sname -> sno
  custid -> custname,custaddr

Because of "custid -> sno" the dependency "sno,partno,custid -> quantity" can be modified to "partno,custid -> quantity".

These relations are normalised into 2NF as follows:

1. Supp-part(sno,partno)
   Cust-supp(partno,custid,quantity)
   Part(partno,partdesc)
   Cust(custid,custname,custaddr)
    
2. Supp-part(sno,partno)
   Cust-supp(partno,custid,sno,quantity)
   Part(partno,partdesc)
   Cust(custid,custname,custaddr,sno)
    
3. Supp-part(sno,partno,partdesc)
   Cust-supp(partno,custid,quantity)
   Cust(custid,custname,custaddr,sno)
    
4. Supp-part(sno,partno)
   Cust-supp(partno,custid,quantity)
   Part(partno,partdesc)
   Cust(custid,custname,custaddr,sno)
    

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