I have a load of data and i need 2 put this into first normal form. However all the examples i see it just shows 1nf either as ONE big table or TWO tables.
Is there any certain rule for the amount of tables/entities that 1NF can have??
My database is to do with a flight booking system so theres loads and loads of info for the flight, then the airport details and the aircraft details and it just looks wrong in 1 big table or 2 tables.
I'd shoot for third normal form rather than first normal form. There is no point trying to do real work with a design that you know is going to need overhaul before you hit production!
As in all normal forms, the limit on the number of tables is "enough"... When you have enough tables, you are good to go. A good rule of thumb is to think of the objects you are trying to represent (airports, planes, flights, etc). You need at least that many tables.
Thanks for your replys. The database i have to show in 1nf, 2nd and 3rd. I think straight to third normal form really and find it hard to think in 1 and 2. Does everyone reckon that for 1nf i should have 3 tables called flight, airport and aircraft? and there work from there? Below is the information that i need 2 record.
Basically the flight has flight number, depart time, arrival time, dest airport, arrival airport
The airport will have city, country, runway number
Aircraft has a description of it such as number of seats, flight make etc and national or international aircraft.
But also i need a table for completed flights and future flights, i find this weird at 1nf about where 2 add it in to those 3 tables, the tables will just be really big!!
Then for 3nf i was going to add a table for country as some countries have more than one airport and this could become duplicate.
I hope this makes sense to someone lol as its confusing me!