SQL | Aggregation and grouping exercise | Show the number of events for each category

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.

You can learn how to do this exercise if you attend one of more of the courses listed below!

Software ==> SQL  (198 exercises)
Version ==> Any version of SQL Server
Topic ==> Aggregation and grouping  (8 exercises)
Level ==> Relatively easy
Courses ==> Introduction to SQL  /  Fast-track SQL
Before you can do this exercise, you'll need to download and unzip this file (if you have any problems doing this, click here for help). Once you've done this:
  1. Go into SQL Server Management Studio;
  2. Open the SQL file you've just unzipped (you can press CTRL + O to do this); then
  3. Execute this script.

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).

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Create a query which:

  • groups by the category name from the category table; and
  • counts the number of events for each.

You'll need to create a join between the tblCategory and tblEvent tables to do this.

Here's what you should see if you sort your query to show the categories with most events first:

First few events

The first few categories returned by your query. Politics trumps everything.

 

Save this query as Politics and disaster, then close it down.

You can unzip this file to see the answers to this exercise, although please remember this is for your personal use only.
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