SQL | Variables exercise | Retrieve aggregated data using variables

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.

Software ==> SQL  (198 exercises)
Version ==> Any version of SQL Server
Topic ==> Variables  (8 exercises)
Level ==> Relatively easy
Subject ==> SQL training
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  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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The aim of this exercise is to summarise events using the MIN, MAX and COUNT functions:

Variable Aggregate

The snag?  You're not allowed to use GROUP BY!

To do this, create variables to hold each of the aggregates:

Variable What it will hold eventually
@EarliestDate The earliest date
@LatestDate The latest date
@NumberOfEvents The number of events
@EventInfo The title Summary of events

Now use a single SELECT clause to set the value for all of these variables (alternatively you could use a series of subqueries).

Write another SELECT clause to show the value of the variables, to show the summary output shown above.

Optionally save this as The early, the late and the rest.sql 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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23 Nov 18 at 13:33


I'm having trouble getting this exercise done.

Is there anywhere i can get the solution? 

16 Dec 18 at 07:26

 use WorldEvents
  declare @EarliestDate datetime
  declare @latestDate datetime 
  declare @NoOfEvents int
  declare @Eventimfo varchar(max)='Summary of event'

   select @EarliestDate=min( cast(EventDate as date)) from dbo.tblEvent 
  select @latestDate=max(cast(EventDate as date))  from dbo.tblEvent
  select @NoOfEvents=count(EventID) from dbo.tblEvent

  select @Eventimfo as Title, @EarliestDate as EarliestDate,@latestDate as latestDate,@NoOfEvents as NoOfEvents

23 Nov 18 at 15:12

We don't post the answers to exercises (as you'll have noticed) - partly because there has to be some reason to attend our courses, but also because it would remove the incentive to work at finding a solution.  For the same reasons we usually don't post prospective answers, but since you ask nicely ... anyone out there able to help and post a solution?