October 12th, 2013, 04:42 PM
ERD Relational Entity Question
Design a database to keep data about college students their academic
advisors, the clubs they belong to , the moderators of the clubs and
the activities that the clubs sponsor. Assume each student is assigned
to one academic advisors, but an advisors counsels many students .
Advisors do not have to be faculty members. Each student can belong to
any number of clubs , and the clubs can sponsor any number of
activities. The club must have some students members in order to
exist. Each activity is sponsored by exactly one club, but there
might be several activities scheduled for on day . Each club has one
moderator, who might or might no be a faculty member . Draw a complete
E-R diagram for this example . include all constraints .
IV Why donít the others need to be placed in a table? How will
you deal with them? Change the schema above if necessary.
Others become attributes in the table
V Create the table for that one relationship that must be
placed in a table.
Is it Faculty table or non Faculty table?
I need to know which table needs to be added?
Greatly appreciate your time and efforts
October 12th, 2013, 05:59 PM
incomprehensible homework question is incomprehensible
October 12th, 2013, 06:04 PM
I can post the ER diagram but the site is not letting my post any image or url but if you want to see it go here
Originally Posted by r937
October 13th, 2013, 11:44 AM
The only relationships that needs to be put into a table is the M to M relationship Belongs.
If a relationship is 1 to M, it is advisable to put the primary key of the entity on the "1" side into the entity on the M side. Thus, one adds an attribute(s) to the M side entity for the key to the 1 side. For example, if an activity is sponsore by one and only one club, then why not put the key to club clubname into the Activity entity set? It saves redundancy, since if you put up a table for Sponsors, then this table needs at minimum the keys from the two participating entities.