Draw an extended ER model for the example scenario
provided. using this extended notation.
Draw a TREND data model for the following description:
Flight is an entity type whose objects will always be a
flight.
Client is an entity type whose objects will always be a
client.
Traveller is a client.
Previous-customer is a client.
VIP-customer is a client.
Each traveller is not a traveller for some time.
Each previous-customer is not a previous-customer for some
time.
Each VIP-customer is not a VIP-customer for some time.
A client may also become a traveller.
A client may also become a VIP-customer.
Each traveller must evolve to a previous-customer ceasing
to be a traveller.
A previous-customer may also become a traveller.
A previous-customer may also become a VIP-customer.
Each VIP-customer was already a previous-customer.
Each VIP-customer was already a traveller.
A traveller books a flight A traveller pays for a flight.
A previous-customer took a flight.
Each traveller books a flight will be followed by traveller pays
for flight after exactly 3 days, terminating the traveller books a
flight relation.
Each previous-customer took a flight must have been
preceded by traveller pays for flight, and terminating that
traveller pays for flight relation.
Each object in entity type client having attribute company
does not have a company at some time.
Each object in entity type flight having attribute delay has
delay at all times.
Once the value for arrival time is set, it cannot change
anymore
Draw an extended ER model for the example scenario provided. using this extended notation. Draw a TREND data model for t
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answerhappygod
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Draw an extended ER model for the example scenario provided. using this extended notation. Draw a TREND data model for t
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