Lesson 8. Using Data Manipulation Functions
In this lesson, you’ll learn what functions are, what types of functions DBMSs support, and how to use these functions. You’ll also learn why SQL function use can be very problematic.
Understanding Functions
Like almost any other computer language, SQL supports the use of functions to manipulate data. Functions are operations that are usually performed on data, usually to facilitate conversion and manipulation.
An example of a function is the RTRIM()
that we used in the last lesson to trim any spaces from the end of a string.
The Problem with Functions
Before you work through this lesson and try the examples, you should be aware that using SQL functions can be highly problematic.
Unlike SQL statements ...
Get Sams Teach Yourself SQL in 10 Minutes, Fourth Edition 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.