#testseries

Question

Consider the following E-R diagram:

 

What is the minimum relations required which satisfied the 2^nd normal form?

A)	1
B)	2
C)	3
D)	4

Comments

yups..

---

Suppose if it were asked to cal number of tables for BCNF with same diagram except that C should be single valued then we will have 3 tables

E1((A)BC)

R((AD))

E2((D)EF)

because if we merge all in one then that will be in 1nf but not even 2nf because of PDs

A--> BC

D --> EF

ryt.

---

yes, correct.

Answer 1

There will be 4 tables as follows:

$E_1$(A,C) (for mutivalued attribute C)

$E_1$(A,B)  

$E_2$(D,E,F) 

R(A,D)  (for m:n relationship )

Comments

Here relationship type is not given. Are we supposed to think it as m:n relationship?

---

how 3?

if there are no arrows it means many to many relationship.

---

line without arrow head (------------) means 'n'

line with arrow head (----------->) means '1'

Answer 2

3 table is required

Answer 3

4 table is required --

R1(A,B)

R2(A,C)

R3(A,D) 

R4(D,E,F)