Separate PK in Jxn Tbl?
I always use just the 2 primary keys but....
If I were a library lending 2 undiffentiatable copies of 1 book to the same
person, I suppose I would need an Autonumber PK plus A BookID and
BorrowerID.
Phil
"Neil" wrote in message
. ..
Whenever I've created junction tables in the past, I always made the PK of
the junction table the combined pks from the two other tables. Ex: Table1
PK=A; Table2 PK=B; Junction table consists of two fields, A and B, which
together comprise the PK for the junction table.
However, I just came across some code in which the person created a
junction table with a separate PK consisting of an autonumber field, and
then the two fields.
So I was wondering how others did junction tables -- with a standalone
autonumber PK, or with a PK consisting of the PKs of the tables being
joined? And, if a standalone PK, then why?
Thanks!
Neil
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