Comparing values
eSymphony has asked you to look into the differences between composer and artist name. More specifically, they want to know for which Queen tracks these differ. If they are the same a NULL
value should appear, and if they differ the artist name should be displayed. This is obviously no challenge for you since you know all about null-related functions.
Diese Übung ist Teil des Kurses
Introduction to Oracle SQL
Anleitung zur Übung
- Display
NULL
if the artist name and composer are the same and the artist name if they differ. - Filter on rows where the artist name is
'Queen'
.
Interaktive Übung
Versuche dich an dieser Übung, indem du diesen Beispielcode vervollständigst.
-- Use the correct null-related function
SELECT t.Name, ar.Name, t.Composer, ___(___, ___)
FROM Track t INNER JOIN Album a
ON t.AlbumId = a.AlbumId
INNER JOIN Artist ar
ON a.ArtistId = ar.ArtistId
-- Filter on artist name Queen
WHERE ___ = '___'
ORDER BY 3