Database Systems – Discussions

Discussion 1: Create a discussion thread (with your name) and answer the following question(s): (Chapter 3):  

Consider the ER diagram shown in Figure 3.22 for part of a BANK database (also below for reference). Each bank can have multiple branches, and each branch can have multiple accounts and loans.

(a) List the strong (nonweak) entity types in the ER diagram.

(b) Is there a weak entity type? If so, give its name, its partial key, and its identifying relationship.

(c) What constraints do the partial key and the identifying relationship of the weak entity type specify in this diagram?

(d) List the names of all relationship types, and specify the (min,max) constraint on each participation of an entity type in a relationship type. Justify your choices.

Discussion 2: Create a discussion thread (with your name) and answer the following question(s):

Discussion 1 (Chapter 5):  Discuss the characteristics of relations that make them different from ordinary tables and files. 

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