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db design problem [message #225510] Tue, 20 March 2007 03:29 Go to next message
Moali72
Messages: 2
Registered: March 2007
Junior Member
hi,
i have problem in design db of my system
here what i have:

i have customers with many branches &
each branch has many machines &
each machine exists in many branches

Also : each machine has many components
each component exists in many machines

Also each branch has many machines with it's components , and each component in this branch machine has it's serial Number

now how i draw this as i am confused

thx ,waiting for your apprecaited reply
Re: db design problem [message #225644 is a reply to message #225510] Tue, 20 March 2007 12:46 Go to previous messageGo to next message
Frank
Messages: 7901
Registered: March 2000
Senior Member
This depends on whether you are doing a functional design (Entity modelling) or a technical design (Table modelling). In an Entity-Relation Diagram, you can draw an n to m relation between two entities (e.g. machine and component)

In a technical design, you would create an intermediate table between the machines- and components tables. In this you have two columns: the PK-column of the machines table and the PK column of the components table.
icon5.gif  Re: db design problem [message #225706 is a reply to message #225644] Wed, 21 March 2007 01:46 Go to previous messageGo to next message
Moali72
Messages: 2
Registered: March 2007
Junior Member
i need the technical desgin but mainly for

each branch has many machines with it's components ,
and each component in this branch machine has it's serial Number


and do't forget that
each machine has many components
each component exists in many machines

thx
Re: db design problem [message #306816 is a reply to message #225510] Mon, 17 March 2008 00:11 Go to previous message
marco123jacob
Messages: 1
Registered: March 2008
Junior Member
I too have the same problem......
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