WISE OWL EXERCISES
SQL EXERCISES
SQL EXERCISES
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SQL | Subqueries exercise | Selecting data from a sub query
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| Software ==> | SQL (198 exercises) |
| Version ==> | Any version of SQL Server |
| Topic ==> | Subqueries (5 exercises) |
| Level ==> | Average difficulty |
| Course ==> | Introduction to SQL |
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Write a SELECT statement to return events from the 3 continents with the fewest events. To do this first write a SELECT query which returns all the continents and events.
Unsorted results returns 459 events.
Now underneath write another SELECT statemnt which lists events for the 3 continents with the lowest COUNT of events. Put the COUNT in the ORDER BY clause, not the SELECT.
Not as many penguin parties as you'd expect.
Finally use the second SELECT as a filter in the first SELECT's WHERE clause. To do this use ContinentName IN (Sub Query).
Only 8 events in these 3 continents - maybe stick to Ibiza and the Islands!
Optionally save this as Quiet places to visit.sql, and close it down.
i cannot seem to figure out the answer of the second one this is my code so far :
select top 3 con.ContinentName, eve.EventName
from tblCountry as cou
inner join tblContinent con on con.ContinentID=cou.ContinentID
inner join tblEvent as eve on eve.CountryID=cou.CountryID
select top 3 cou.CountryName
from tblCountry as cou
inner join tblEvent as eve on eve.CountryID=cou.CountryID
group by cou.CountryName
order by count(eve.eventid) desc