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

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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
Classroom ==> Introduction to SQL  /  Fast-track SQL
Online ==> 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.

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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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FloridaMan   Reply to FloridaManReply
23 Sep 21 at 12:34

select c.CategoryName as Category_Name

  , count(c.CategoryName) as Number_of_events

from [dbo].[tblEvent] e

left join [dbo].[tblCategory] c

on e.CategoryID = c.CategoryID

group by c.CategoryName

order by Number_of_events desc

***BOOM,DONE***

FadwaEgypt   Reply to FadwaEgyptReply
23 Oct 21 at 19:35

EXCELLENT

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