SQL | Archived exercise | Show number of events by country, with HAVING

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 on the relevant Wise Owl classroom training course (sadly for the moment only in the UK).

Software ==> SQL  (198 exercises)
Version ==> Any version of SQL Server
Topic ==> Archived  (70 exercises)
Level ==> Average difficulty
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).

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If you haven't already got it set up in SQL server, restore the Historical Events database from the above folder.

Create a query to show for each country the number of events occurring since 1st January 1990, but only for countries having 5 or more events:

SQL exercise - Aggregation and grouping (image 1)

You will need to use a WHERE and a HAVING clause to get these results

Save this query as Recent events, then close it down.

If you still have the time and energy, create another query which shows the number of events for each event name length, with the most common character length (the mode) first:

SQL exercise - Aggregation and grouping (image 2)

More events have a name with 32 characters than any other

Save this as Grouped by length and 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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