Transitive dependencies in DBMS

What is transitive dependency

When an indirect relationship leads to functional dependency, it is called transitive dependency.

If P -> Q and Q -> R are true, then P-> R is a transitive dependency.

To achieve 3NF, eliminate transitive dependencies.

Example

##M08M03M05The above table is not in 3NF because it has transitive functional dependencies -

##Movie_ID td>	Listing_ID	Listing_Type	DVD_Price ( $)
##L09 >	Crime	180 >
M03	L05	Drama	250
L09	Crime	##180

Movie_ID -> Listing_ID Listing_ID -> Listing_Type##Therefore, the following Has transitive functional dependence.

Movie_ID -> Listing_Type

To remove the violation, you need to split the tables and remove the transitive functional dependency.

Movie_ID

180##M05L09Listing_ID

##DVD_Price ($)	M08 L09
	##M03	L05 250
		180
		##

Listing_Type

##L09CrimeDramaNow the above relation is in Third Normal Form (3NF) of Normalization.

L05
##L09	Crime

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