Adam, Alan,

>If TableB contains some other fields, then I can understand the
>structure. If however there are no other fields aside from the
>FIELDID in tableB, then I don't know what is achieved by creating the
>table in the first place.

>Normalisation 101: Duplicated data is often a sign that the database
>structure needs to be normalised.

In effect is tableA that contains more data (columns).
TableB contains the same data of TableA but not ALL the data.
As said and simplifing the structure (that obviously is more complex):

TableA
FieldID FieldA FieldB FieldC

TableB
FieldID FieldA(the same of tableA) FieldC(the same of tableA)
It does not contains FieldB

At this point It would be correct to create (for normalisation database) one
only table and leave blank FieldB when not necessary (for the contability
movement of tableB that do not need it) ?

Thank you very much for your help
Adriano


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