Copyright

Ch 6: Removing Data in SQL

About This Chapter

This short tutorial chapter helps you understand how to remove data in SQL. These brief and engaging lessons help you quickly learn and understand the functions of SQL's data removal processes.

Removing Data in SQL: Chapter Summary

The lessons in this chapter show you how data is deleted in the SQL programming language. By defining concepts like the DELETE statement and DROP database, our instructors walk you through the various methods programmers use to remove data in SQL. Each lesson outlines the purpose and function of a particular method, then shows you how the task is carried out.

Our SQL instructors offer concise and to-the-point instruction so you can learn quickly and efficiently. Each lesson comes with a short quiz you can take to make sure you fully understand the statements, indexes and tables you learn about.

The lessons in this chapter will help you:

  • Know what the DELETE statement does
  • Understand DROP index and DROP database
  • Assess the purpose of DROP columns and rows
  • Recognize DROP constraint and DROP view
  • Analyze DROP table and temp table
  • Explain TRUNCATE string and TRUNCATE table

9 Lessons in Chapter 6: Removing Data in SQL
Test your knowledge with a 30-question chapter practice test
SQL: DELETE Statement

1. SQL: DELETE Statement

Explore how and what the SQL Delete statement does. The SQl Delete is only used in large, interconnected, relational databases where permanent removal is warranted. There is no trash can from which to recover records or files if it is implemented.

SQL DROP Index & DROP Database: Tutorial

2. SQL DROP Index & DROP Database: Tutorial

We collect and organize information, lots of it. So it makes sense that we'll want to delete some of it at times. In this lesson, we'll take a look at SQL, indexes, databases, and how the DROP command affects them.

SQL DROP Columns & Rows: Tutorial

3. SQL DROP Columns & Rows: Tutorial

This lesson reviews the syntax for dropping columns and rows from a database using SQL. Deleting a column removes a data field; removing a row deletes a record of data.

SQL DROP Constraint: Tutorial & Overview

4. SQL DROP Constraint: Tutorial & Overview

In this lesson, we will learn about the SQL drop constraint command, which is used to remove the constraint that limits the kind of data that can be saved in a database table.

SQL DROP Table: Tutorial & Explanation

5. SQL DROP Table: Tutorial & Explanation

How can you keep your database from being overrun with information? Make some space with DROP TABLE! This lesson will discuss the SQL process for dropping a table (DROP TABLE). The basic syntax will be discussed, as well as examples from two major database systems: Oracle and SQL Server.

SQL DROP Temp Table: Tutorial & Explanation

6. SQL DROP Temp Table: Tutorial & Explanation

A temporary table should only be temporary: when it's no longer needed, drop it. This lesson covers how to drop a temporary table in SQL, including syntax and examples.

SQL DROP View: Tutorial & Overview

7. SQL DROP View: Tutorial & Overview

The SQL DROP command may be one that asks for caution, since it removes data. However, dropping a View does not delete the source data. This lesson will cover the DROP View command, providing an overview and examples.

SQL TRUNCATE String: Tutorial & Overview

8. SQL TRUNCATE String: Tutorial & Overview

SQL offers some nifty commands to manipulate and work with strings. In this lesson, we'll discuss three commands, each with their own uses, that can reduce strings to an appropriate size.

SQL TRUNCATE Table: Tutorial & Explanation

9. SQL TRUNCATE Table: Tutorial & Explanation

This lesson will cover the SQL TRUNCATE statement, providing a brief tutorial of the command and some code examples from various database management systems.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Other Chapters

Other chapters within the SQL Tutorial & Training course

Support