SQL | Views exercise | Create a series of views to get at interesting episode data

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 ==> Views  (5 exercises)
Level ==> Harder than average
Subject ==> SQL training
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 done so, run the script in the above folder to generate the Doctor Who database.

Create a series of views which will ultimately list out all of the episodes which had both multiple enemies and multiple companions.

There are many ways to do things like this in SQL, and the method in this exercise is a long way from being the most efficient!

To achieve this, create (in this order) the following views:

View What it must do
vwEpisodeCompanion Llist all of the episodes which had only a single companion.
vwEpisodeEnemy List all of the episodes which had only a single enemy.
vwEpisodeSummary List all of the episodes which have no corresponding rows in either the vwEpisodeCompanion or vwEpisodeEnemy tables.

When you select all of the rows selected by the vwEpisodeSummary view in title order, you should see the following:

The episodes returned

The first few of the 14 episodes returned by this view.


This exercise should reinforce the fact that you can use tables and views interchangeably in script.

If you've created one script to do all of this (as the answer does), save this as Singular episodes 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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