Exercise: Show number of events by country, with HAVING

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Category ==> SQL  (115 exercises)
Topic ==> Aggregation and grouping  (6 exercises)
Level ==> Average difficulty
Course ==> Introduction to SQL
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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.

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