Why Is Sno, Pno=>Qty, Sname=>Qty in 3NF?

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SUMMARY

The discussion centers on the normalization of database tables into Third Normal Form (3NF) using functional dependencies (FDs). The FDs presented are Sno,Pno=>Qty, Sname,Pno=>Qty, Sno=>Sname, and Sname=>Sno. While the first two FDs satisfy the 3NF criteria, the last two do not, as they do not maintain the requirement that the left-hand side (LHS) must be a super key and the right-hand side (RHS) must be a non-prime attribute. The confusion arises from the interpretation of Sname as a potential lookup table, which complicates the assessment of 3NF compliance.

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shivajikobardan
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Homework Statement
3NF third normal form
Relevant Equations
none
Sno,Pno=>Qty
Sname,Pno=>Qty
Sno=>Sname
Sname=>Sno

To be in 3NF, LHS should be super key and RHS should be non-prime attribute.
It holds true for first 2 FDs. But for the last two, it doesn't hold true. So, why is it in 3NF?
chatGPT says it holds true for all FDs, but I can't see how.
 
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The last two look like lookup tables to translate between sno and sname. Given sno I can find sname and given sname I can find sno.
 
shivajikobardan said:
Homework Statement:: 3NF third normal form
Relevant Equations:: none

Sno,Pno=>Qty
Sname,Pno=>Qty
Sno=>Sname
Sname=>Sno
This is impossible to answer without knowledge of what data are contained in the columns, however assuming Sname represents a person's name, and given the fact that two people can have the same name what do you think about your statement that Sname,Pno=>Qty is in 3NF?
 

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