The join table has one-to-many relationships with both of the
tables involved in the many-to-many relationship. This principle can be a bit confusing at first, but
close examination of Figure 3-12 soon reveals the beauty of this arrangement.
In Figure 3-12, you can easily see that student ID 2 (Michael Barde) belongs to the music club,
while student ID 12 (Jeffrey Wilson) is a member of the horticulture club. Both Michael Barde and
Jeffrey Wilson belong to the photography club. Each student belongs to multiple clubs, and each
club contains multiple members.
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Access Building Blocks Part I
Because of the additional complication of the join table, many-to-many relationships are often considered
more difficult to establish and maintain. Fortunately, Access makes such relationships quite
easy to establish, once a few rules are followed. These rules are explained in various places in this
book. For instance, in order to update either side of a many-to-many relationship (for example, to
change club membership for a student), the join table must contain the primary keys of both tables
joined by the relationship.
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