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Database :Conceptual schema

Once a database designer is aware of the data which is to be stored within the database, they must then determine where dependancy is within the data. Sometimes when data is changed you can be changing other data that is not visible. For example, in a list of names and addresses, assuming a situation where multiple people can have the same address, but one person cannot have more than one addresses, the name is dependent upon the address, because if the address is different then the associated name is different too. However, the other way around is different. One attribute can change and not another.