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Titre:
Why not AutoIncrement PK inside a table?
Right now I use a call to a stored procedure in the DBC
to get the next sequential primary key (PK). The technique
I am using is nearly the same as that used in the TasTrade
app supplied with VFP - nothing fancy.
Why is it that the auto incrementation is not contained
inside the DBF header? The RECCOUNT() value is returned
from and updated in the header. Seems like adding an
additional column (like done with whether a column can
accept .NULL. values) to ID the PK would be fairly easy
to do. Also, an additional 4 bytes of space in the header
can contain the 0 - 2,000,000,000+ values when using
integer keys.
Just curious why this has not been done before. I recall
that trying to add a PK via ASP was not possible. At least
not the way I tried it. Since the integer surrogate PK value
would be totally encapsulated within the DBF header that
problem would go away.
Seems like this would be a nice feature to add to VFP 7...
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