Exercise: Create a scalar function to determine type of each episode

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.

The answer to the exercise will be included and explained if you attend the Wise Owl course listed below!

Category ==> SQL  (115 exercises)
Topic ==> Scalar functions  (6 exercises)
Level ==> Average difficulty
Course ==> Advanced SQL
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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 create a function called fnEpisodeDescription such that you can count how many episodes there are of each type:

-- count number of episodes of each type

SELECT

dbo.fnEpisodeDescription(Title) AS 'Episode type',

COUNT(*) AS 'Number of episodes'

FROM

tblEpisode

GROUP BY

dbo.fnEpisodeDescription(Title)

Here's what this should return:

List of episodes by type

It's reassuring to see that the number of first and second parts are the same!

 

To write this function use the CHARINDEX function to determine whether one string of text exists within another:

The episode titles

Your function should look for the word Part 1 (or failing that, Part 2) in the title passed in.

 

As a guide, CHARINDEX('owl','Wise Owl') would return 6, whereas CHARINDEX('fox','Wise Owl') would return 0.

When you've got your function and query working, save (optionally) the SQL as Part of a couple.sql, then close it down.

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