Also keep in mind that a US SSN is not unique (there are cases of duplicate SSN beeing issued) so it is not reccomended to use the SSN as a PK.

>Beware that SSN is considered "sensitive" data and if your system doesn't actually need it (i.e. for taxpayer identification), you might want to make it an optional field.
>
>Privacy concerns are high in the US and likely to get worse, and many people will refuse to give their SSN.
>
>Dan
>
>>Dear all
>>
>>I am translating my software to English and also making some
>>structural changes to it in order to reach american users
>>
>>In Brazil our national indenfication document is CPF.
>>CPF is a 11 digits string that has a logic and is possible to validate by a function.
>>
>>I would like to know if SSN is also a logic string, and a function in VFP is available to validade it
>>
>>Regards
>>
>>Moises