Read our blogs, tips and tutorials
Try our exercises or test your skills
Watch our tutorial videos or shorts
Take a self-paced course
Read our recent newsletters
License our courseware
Book expert consultancy
Buy our publications
Get help in using our site
549 attributed reviews in the last 3 years
Refreshingly small course sizes
Outstandingly good courseware
Whizzy online classrooms
Wise Owl trainers only (no freelancers)
Almost no cancellations
We have genuine integrity
We invoice after training
Review 30+ years of Wise Owl
View our top 100 clients
Search our website
We also send out useful tips in a monthly email newsletter ...
Software ==> | SQL (203 exercises) |
Topic ==> | Triggers (2 exercises) |
Level ==> | Average difficulty |
Subject ==> | SQL training |
This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.
This will generate the database that you'll need to use in order to do this exercise (note that the database and script are only to be used for exercises published on this website, and may not be reused or distributed in any form without the prior written permission of Wise Owl).
The aim of this exercise is to use a trigger to write any country changes made into a separate table. Here is what the table should show if you rename Vietnam to Viet Nam and then insert and delete the (to date) fictitious country OwlLand:
What the log table should show after these changes.
To start the ball rolling, create the table shown above with two columns:
Column | What it should contain |
---|---|
CountryName | The name of the country just inserted, edited or deleted |
Change | Whether this was inserted, deleted or changed |
Now create a trigger to run after anyone changes a country. This should capture two rows:
Row | Notes |
---|---|
The old country name | Take the deleted table's country name |
The new country name | Take the inserted table's country name |
Note that when you update a table, you populate both the deleted and inserted tables.
Now create two more triggers:
Trigger | What it should do |
---|---|
After insert | Add a row to the changes table containing the new country's name |
After delete | Add a row to the changes table containing the name just deleted |
When you're happy everything's working OK, optionally save your query as Catalonia perhaps.sql, then close it down.
You can find other training resources for the subject of this exercise here:
Kingsmoor House
Railway Street
GLOSSOP
SK13 2AA
Landmark Offices
99 Bishopsgate
LONDON
EC2M 3XD
Holiday Inn
25 Aytoun Street
MANCHESTER
M1 3AE
© Wise Owl Business Solutions Ltd 2024. All Rights Reserved.