
Teach Yourself SQL in 21 Days, Second Edition


Week 3 At A Glance
Applying Your Knowledge of SQL
Welcome to Week 3. So far you have learned the fundamentals of SQL and
already know enough to apply what you have learned to some real-life situations.
This week builds on the foundation established in Weeks 1 and 2. Day 15
shows you how to streamline SQL statements for improved performance. Day
16 talks about the data dictionary, or system catalog, of a relational
database and shows you how to retrieve valuable information. Day 17 extends
the concept of using the data dictionary to generate SQL as output from
another SQL statement. You will learn the benefits of this technique and
discover how generating SQL can improve your efficiency on the job. Day
18 covers Oracle's PL/SQL, or Oracle procedural language. PL/SQL is one
of the many extensions to standard SQL. Another extension is Sybase's and
Microsoft Server's Transact-SQL, which is covered on Day 19. Day 20 returns
to Oracle to cover SQL*Plus, which allows you to use advanced commands
to communicate with the database. SQL*Plus also enables you to format query-generated
reports in an attractive manner. You can use SQL*Plus in collaboration
with PL/SQL. Day 21 examines errors and logical mistakes that relational
database users frequently encounter. We provide brief descriptions of the
errors, solutions, and tips on avoiding errors.


© Copyright, Macmillan Computer
Publishing. All rights reserved.