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Software ==> | SQL (203 exercises) |
Topic ==> | Derived tables and CTEs (19 exercises) |
Level ==> | Average difficulty |
Subject ==> | SQL training |
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.
First (if you haven't already done so) run the script shown above to generate the Doctor Who training database.
The aim of this exercise is to show a list of all of the enemies appearing in Doctor Who episodes featuring Rose Tyler, but not David Tennant.
It's possible - probable, even - that you could do this with a single SELECT statement, but CTEs make it so much easier to divide a complicated query into two simpler parts!
First create a query to show the episode id numbers for the 13 episodes which feature Rose Tyler as a companion, but not David Tennant as the Doctor.
Linking to this as a CTE, show the 8 enemies which appear in these episodes (some more than once):
The enemies corresponding to episodes featuring Rose Tyler, but not David Tennant.
Optionally, save this query as Wonderful CTEs.sql, then close it down.
You can find other training resources for the subject of this exercise here:
Kingsmoor House
Railway Street
GLOSSOP
SK13 2AA
Landmark Offices
99 Bishopsgate
LONDON
EC2M 3XD
Holiday Inn
25 Aytoun Street
MANCHESTER
M1 3AE
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