What languages emerged to standardize the basic network data model
why was such standardization important to users and designers?
5. Describe the basic features of the relational data model and discuss their importance to the end user and the designer.
6. Explain how the entity relationship (ER) model helped produce a more structured relational database design environment.
7. Use the scenario described by “A customer can make many payments, but each payment is made by only one customer” as the basis for an entity relationship diagram (ERD) representation.
8. Why is an object said to have greater semantic content than an entity?
9. What is the difference between an object and a class in the object-oriented data model (OODM)?
10. How would you model Question 7 with an OODM? (Use figure 2.4 as your guide.)
11. What is an ERDM, and what role does it play in the modern (production) database environment?
12. In terms of data and structural independence, compare file system data management with the five data models discussed in this chapter.
13. What is a relationship, and what three types of relationships exist?
14. Give an example of each of the three types of relationships.
15. What is a table, and what role does it play in the relational model?
16. What is a relational diagram? Give an example.
17. What is logical independence?
18. What is physical independence?
19. What is connectivity? (Use a crow’s foot ERD to illustrate connectivity.)