1. Is it possible for two entities to be related to each other in two ways? For example, could entity A be related to entity B both 1:M and 1:1 at the same time?
a. No, this would violate structural integrity.
b. Yes, but this should be avoided where possible.
c. Yes, this is a perfectly acceptable practice when called for.
d. Yes, this is very desirable and should be sought after.
a. is at most in first normal form.
b. is also in second normal form.
c. cannot be in third normal form.
d. must be in fourth normal form.
3. Assuming common business practices, the connectivity of the relationship between publishers and books is most likely to be:
4. E-R Diagrams are oriented reward which of the following data models?
a. Conceptual level.
b. Internal level.
c. External level.
d. Physical level.
Relationship between entities, 1NF and Data model of ER is discussed.