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Left outer join

eSymphony's marketing department has noticed that songs in playlists get purchased more often. Since there's a Led Zeppelin anniversary coming up, they want to know how many songs composed by Jimmy Page, the founder of the band, are not in a playlist yet.

You decide to use a left outer join to solve this problem. By doing this, you are sure all tracks, even the ones that aren't included in a playlist, are shown.

说明 1 / 共 2 个

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Perform a left outer join between the relevant tables.
Match the tables on the TrackId field.

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说明 1 / 共 2 个

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