HI, i hope somebody can help me in reviewing my database, because i am not sure at all if it is correct and i really need it to be within thursday because i have to deliver it to my teacher. First of all sorry if my english won't be very good but it is not easy to explain such problems in another language
Ok i try to focus on the request:
I need a database for a firm to let it manage its orders.
The firm can have many clients, at the moment each client works for his firm but i have to contemplate the possiblity that this client changes his company in the future. Each client can make one request composed by one or more products.
When the owner of my firm receives this request, he creates a document called "commessa" identified by
- a code for "commessa commerciale"
- a code for "sottocommessa commerciale"
- a code for "studio"
this is the logic -> when a client contacts him he gives a "commessa commerciale" code (that he chooses, ie "06001"), and by default a "sottocommessa" code "A", and a "studio" code "1". if the request 06001 is made by different products they will have a different letter of "sottocommessa" ie
- pencils -> A
- pens -> B
not being a firm of "simple" products, the owner must study the case and then he makes a proposal to the client. If the client accepts, this request will become operative with its code "operativo", and it will be a real order.
If the client wants some changes, the owner will study again the case changing the "studio" code ,from "1" to "2" for example, and so on. If the client refuses, the original "commessa" will be stored just for statistics reasons.
i hope to have been enough clear to make the situation understandable.
i attach my er-diagram with all the tables i though. For the language it is not a problem i will do it in mysql, i just need to know if the implementation of the tables (foreign keys, normalization bla bla) are correct because i am really out of practise in it, and i have received enough insults last week from my teahcer
Thanks to everybody who will be so patience to think about it and answer me
PS I translated in the document just the important attributes to make it understand. Hope to be enough.