>Hi,
>What about the auto-generated value? should I store it in Integer or character?
>
>Beside, should I just use the auto-generated value as forgeign key? For example in stock in table, should I place ItemCode ? Do you think place itemcode in stockin table will easier the error checking?
>
>Any comments?
>
>Thank you

My personal recommendation - many programmers use this method, and many others don't:

Use an integer, auto-generated, for the primary key of each table (or most tables). Don't show this key to the user.

If I call this the primary key, this implies that it is also used as foreign key in other tables.

For example, if you have a list of materials, each material will have a code which the user sees, and assigns - but according to the system I am recommending, this will not be the primary key. For the primary key, you will use an "auto-generated" integer, instead (before VFP 8, this would mean a separate table to store the sequences, a function to do the lookup, and call this function from the field's default value).

For other tables, use this same number as a foreign key. This might include the record of what materials come in and out, and the current stock (if you need to keep track of more than one warehouse).

Greetings,

Hilmar.