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Oracle® SQL by Example, Third Edition by Alice Rischert

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Appendix A. Answers To Self-Review Questions

Lab 1.1 Data, Databases, and the Definition of SQL

A1:

Question

Answer

Comments

1)

a

 

2)

b

A table must always have at least one column. Rows are not required.

3)

b

SQL is a language. For example, SQL*Plus is a software program (which you will learn about in Chapter 2, “SQL: The Basics”) that allows you to use SQL language to interact with the database.

4)

a

Most database systems are multiuser systems.

5)

a

 

Lab 1.2 Table Relationships

A1:

Question

Answer

Comments

1)

b

The entity relationship diagram is a logical model that doesn't deal with physical tables yet, but instead with entities and attributes.

2)

a

Another cardinality notation used to depict a one-to-many relationship is 1:M or 1:N.

3)

a

 

4)

b

The schema diagram ...

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