A functional dependence FD denotes that the value of one or

A functional dependence (FD) denotes that the value of one or more attributes determines the
value of one or more attributes. For instance, A -> B means that A determines B. Using this
notation, identify all functional dependencies in the following table, including the ones between
composite attributes (e.g., X,Y -> Z or vice versa).

(Example: for attribute A, if value is “a” or “e” then the value for attribute C is always “z” or
“r”, respectively. Therefore, A -> C).

Solution

Initial functional dependency

A attrributes c

a------->z

e------->r

a------->z

e------->r

a------->z

e------->r

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AD ------> CD

A D   ------>     CD

a w ------>zw

ew------>rw

aw------>zw

ew------>rw

as------>zs

es------>rs

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AE------>CE

aq------>zq

ep------>rp

at------>zt

eq------>rq

at------>zt

et------>rt

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