Answers to Chapter 1
 | Reviewing It |
| 1: | What is a relational database? |
| A1: | The relational database supports a single, “logical” structure called a relation, a two-dimensional data structure commonly called a table in the database |
| 2: | What is the difference between a primary key and a unique key? |
| A2: | Unlike primary keys, unique keys can contain null values |
| 3: | Who is considered the father of relational databases? What was the first SQL language called? What company produced the first working relational database? |
| A3: | Dr. E. F. Codd, SEQUEL, Relational Systems, Inc (later became Oracle Corp) |
| 4: | The type of SQL used to update data, delete rows, and so on is known ... |
Get Oracle9i™ Development by Example now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
