A trigger can be an excellent way to enforce business rules that require a table to be updated whenever another table is updated.
- [Instructor] Triggers are operations … that are automatically performed … when a specified database event occurs. … Triggers were introduced into the SQL standard in 2003. … Unfortunately, by that time, most database systems … had already implemented triggers, … so each system still has their own syntax. … How triggers are implemented and used … varies significantly from system to system. … So the lessons in this chapter are intended … as an overview to give you a sense of how triggers work, … but your system will be different. … Here in the database editor, … I am using the test database, … and I pasted some SQL statements … from the chapter 10 exercise file. … We're creating couple of tables. … The widget customer table, … it has an ID, name, last order ID. … And the widget sale table has ID, item ID, … customer ID, which links the customer table, … quantity, and price. … And so we're going to create these two tables … and insert three throws into the customer table, … and then we'll take a look at the customer table. …
This course was created by Bill Weinman. We are pleased to offer this training in our library.
- How databases are organized
- Selecting rows and columns
- Creating new tables
- Inserting and updating data
- Sorting and filtering
- Accessing related tables with JOIN
- Working with strings
- Understanding numeric types
- Using aggregate functions and transactions
- Automating data with triggers
- Creating views
- Using CRUD functions
Skill Level Beginner
2. SQL Overview
3. Fundamental Concepts
7. Dates and Times
Dates and times2m 6s
11. Views and Subselects
12. A Simple CRUD Application
- Mark as unwatched
- Mark all as unwatched
Are you sure you want to mark all the videos in this course as unwatched?
This will not affect your course history, your reports, or your certificates of completion for this course.Cancel
Take notes with your new membership!
Type in the entry box, then click Enter to save your note.
1:30Press on any video thumbnail to jump immediately to the timecode shown.
Notes are saved with you account but can also be exported as plain text, MS Word, PDF, Google Doc, or Evernote.