BDM Problem

[Jose Jim�nez]

I don�t understand the relation one to one between flight and equipment AND 1 -> 1..* between equipment and seat. If one flight is realized by a equipment ( airplane ), then a customer only can reserved a seat of equipment. Why exist the 1--> 1..* relation between equipment and seat ? One customer can reserved more than one seat in a flights ?

[Albert Maurucier]

Equipment means type of aircraft, the association Equipment 1---1..* Seats means a specific aircraft type with a specific seating configuration.
Said more simply: Based on a description, you create an instance of a specific configuration and allocate it to the flight

Hope this help
Albert

[Jose Jim�nez]

Thanks Albert, but my doubt round about if BDM is based to a reservation of a concrete client. I explain me... I have thought create a aircraf association with a equipment but, if I think in a particular client this association will be 1..1 but if I thought it in the airport general system ... one aircraft could have several equipment (configuration aicraft), no ? Can you explain me this ?

[Siddhartha Bhattacharya]

Not really. One aircraft/flight maps to one Equipment.
We are not designing for Boeing ;-) . Its a travel reservation company.
Think from their perspective. What could they possibly do with Aircraft <=> equipment design? Keep it simple..

[Jose Jim�nez]

Well, then if everything is related to the reserve of a client, then following would be correct,no?

AirlineCompany 1 -> 1 Aircraft 1 ->1 equipment 1->1 flight

[Siddhartha Bhattacharya]

I don't know if you are working on the assignment for SCEA and your question is directed at that but here are my 2 cents on a generic scenario

AirlineCompany 1 -> * Aircraft 1 -> 1 equipment

A Flight is related to bookings created
1 Booking -> * Segment 1 -> 1 Flight -> 1 Equipment 1 -> * Seat

[Albert Maurucier]

An airline company has a seat inventory system, seats are allocated to each flight and only to this flight (more accurately to each flight leg). How can you design this?
Aircraft has a property SeatMap (or SeatLayout...).
Equipment has a property Seats.

Regards
Albert

[Jose Jim�nez]

Thanks Albert, ... In the class diagram ... is diferent association 1->* than agregation , why ?? Example between AirlineCompany and Aircraf , or between Sucursal and TravelAgent?? What is most correct 1->* or Agregation.

An other question, In my class diagram i added the following attributes in the segment class:

sement_id
flight
date
time
itinerary_ID
equipment_id
no_seat
equipment_id

is said,... in segment table (B.D) save the datas referent to each flight ,equipment, seat choose for the client for each flight leg . Is that correct ?

[Albert Maurucier]

Hi Jimenez

Sorry, i can't answer, here we go in the details of the assignment, this forum has rules...
You have to make decisions on your definitions of concepts...
Good luck and go ahead.

Regards
Albert

[Jose Jim�nez]

I have a new basic doubth about BDM of SCEA assigment:

A Flight could be cover much segments ( of different clients ), so the relation segment 1-> 1 flight is not correct, no ? It's a error of BMD ?

[Hitry Mitry]

Starting on the part II.

The BDM seems to make sense (well, almost).

As it was pointed out at the beginning of this thread, "Equipment" probably represents the configuration of an aircraft. What appears to be slightly confusing: the only aircraft-configuration issue that is relevant to the seat-booking problem is the seat map on that particular aircraft at the time it's used for particular flight. But this is already taken care of by availability of multiple seat maps! Thus making "Equipment" redundant.

Has anyone thought about it this way?

[Jose Jim�nez]

In BDM ... Itinerary and Segment could be refered to reservation client, and flight, equipment, seat are catalog tables ???

Is correct my assumption ? I need help. All is confused with this BDM ���

Thanks