Abstract

This tutorial will introduce you to Structured Query Language (SQL) which can be used to query databases!

About This Material

This is a Hands-on Tutorial from the GTN which is usable either for individual self-study, or as a teaching material in a classroom.

Questions this will address

• How can I get data from a database?
• How can I sort a query's results?
• How can I remove duplicate values from a query's results?
• How can I select subsets of data?
• How can I calculate new values on the fly?
• How do databases represent missing information?
• What special handling does missing information require?

Learning Objectives

• Explain the difference between a table, a record, and a field.
• Explain the difference between a database and a database manager.
• Write a query to select all values for specific fields from a single table.
• Write queries that display results in a particular order.
• Write queries that eliminate duplicate values from data.
• Write queries that select records that satisfy user-specified conditions.
• Explain the order in which the clauses in a query are executed.
• Write queries that calculate new values for each selected record.
• Explain how databases represent missing information.
• Explain the three-valued logic databases use when manipulating missing information.
• Write queries that handle missing information correctly.