Questions from Database Systems

Q: What does it mean to say that a database displays both entity

What does it mean to say that a database displays both entity integrity and referential integrity?

Q: Why are entity integrity and referential integrity important in a database?

Why are entity integrity and referential integrity important in a database?

Q: What are the requirements that two relations must satisfy in order to

What are the requirements that two relations must satisfy in order to be considered union-compatible?

Q: Describe the basic features of the relational data model and discuss their

Describe the basic features of the relational data model and discuss their importance to the end user and the designer.

Q: Which relational algebra operators can be applied to a pair of tables

Which relational algebra operators can be applied to a pair of tables that are not union-compatible?

Q: Explain why the data dictionary is sometimes called "the database designer's

Explain why the data dictionary is sometimes called "the database designer's database."

Q: A database user manual notes that, “The file contains two

A database user manual notes that, “The file contains two hundred records, each record containing nine fields.” Use appropriate relational database terminology to “translate” that statement

Q: Using the STUDENT and PROFESSOR tables shown in Figure Q3.8

Using the STUDENT and PROFESSOR tables shown in Figure Q3.8 to illustrate the difference between a natural join, an equijoin, and an outer join.

Q: Create the table that would result from πstu_code(student

Create the table that would result from πstu_code(student).

Q: What is a DBMS, and what are its functions?

What is a DBMS, and what are its functions?