SQL | Derived tables and CTEs exercise | Solve a complex question using CTEs and/or subqueries

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 if you attend one of more of the courses listed below!

Software ==> SQL  (198 exercises)
Version ==> Any version of SQL Server
Topic ==> Derived tables and CTEs  (13 exercises)
Level ==> Harder than average
Courses ==> Introduction to SQL  /  Advanced SQL
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First run the script shown above to generate the Doctor Who training database.

Create a query which lists the David Tennant episodes for which none of the enemies appear in any non-David Tennant episodes:

Episode list

The first few of the 31 David Tennant episodes which don't share any enemies with any other non-Tennant episodes.


There are probably hundreds of ways to do this in SQL, and the answer given doesn't claim to use a particularly efficient one.

Optionally, save this query as Tennant only, then 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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