Task $3(4$ marks$)$

Discovering functional dependencies

Read and analyze the relational schemas listed below. All relational schemas are in $1$NF$.$

For each one of the relational schemas, find all nontrivial functional dependencies valid

in the schemas. You must NOT list the functional dependencies, that can be derived from

the other already listed functional dependencies.

ORDER$($customer#$,$ order#$,$ order$-$date, part#$,$ quantity$)$

A relational table ORDER contains information about the parts ordered by the customers

$($customer#$).$ An order is uniquely identified by an order number $($order#$).$ A part is

identified by a part number $($part#$).$ An order consists of one or more parts. An order is

submitted by a customer on a given day $($order$-$date$).$ A quantity of each part is

determined an attribute quantity.

STUDENT $($student$-$number,

total$-$credits$-$required$)$

A relational table STUDENT contains information about the students. A student is

described by a student number $($student$-$number$)$ and full name $($full$-$name$).$

Each students is enrolled in one degree $($attribute degree$).$ An attribute

total$-$credits$-$required contains information about the total number of credits

that must be collected by a student to get a degree.

CONNECTION$($origin$-$city,

address$-$of$-$bus$-$station$-$in$-$origin$-$city,

destination$-$city,

address$-$of$-$bus$-$station$-$in$-$destination$-$city,

ticket$-$price$)$

A relational table CONNECTION contains information about the bus connections

provided by a transportation company. A description of a bus connection from an origin

city $($origin$-$city$)$ to a destination city $($destination$-$city$)$ includes an

address of bus station at an origin city

$($address$-$of$-$bus$-$station$-$in$-$origin$-$city$)$ and an address of bus station at

a destination city $($address$-$of$-$bus$-$station$-$in$-$destination$-$city$)$ and

ticket price $($ticket$-$price$).$ Assume that each city has one bus station.

SUBMISSION$($subject$-$code, assignment#$,$ student#$,$ full$-$name,

submitted$-$file$)$

A relational table SUBMISSION contains information about the submissions of

assignments implemented by the students. A description of an assignment consists of a

subject code $($subject$-$code$),$ assignment number $($assignment#$)$ and a path to a

submitted file $($submitted$-$file$).$ The submitted files are stored in a different

location. Each submission consists of one file. A student is described by a student number

$($student#$)$ and full name $($full$-$name$).$

Deliverables

A file solution$3.$pdf with the lists of nontrivial functional dependencies valid in

each one of the relational schemas described above.