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  3. Introduction to Oracle SQL
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Removing duplicates

Let's dig a little bit deeper into the database. You want to find out which composers have written a song that is sold by eSymphony.

Since composers can write multiple songs, your results will probably include many duplicate values. If you want to select all unique values from a column, you can use the DISTINCT keyword.

说明 1 / 共 3 个

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  • Select the Composer column from the Track table.