Database Reference
In-Depth Information
ticipation.
Figure 10.60
shows the revised relationship diagram for the EMPLOYEES and
CUSTOMERS tables and also demonstrates how you indicate each type of participation.
Note that you place the symbol representing the type of participation
outside
the symbol
that represents the type of relationship.
Figure 10.60. Designating the type of participation for the EMPLOYEES and
CUSTOMERS tables
The type of participation also applies to a self-referencing relationship, although in a
slightly different manner. Because of the nature of a self-referencing relationship, you des-
ignatethetypeofparticipation
for the primary key and foreign key fields
inthetable.
Figure
10.61
showsarevisedrelationship diagramfortheSTAFFtableyouworkedwithearlier in
this chapter.
