This point isn't to do with your structure per se, but it's an important aspect of good database design. If you're using MySQL 5 you can setup relationships with cascades so that you can automatically update/delete related records. For example, with cascade deletes you can delete an artist, and MySQL will automatically delete the related records from the songs and albums table.

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Any fool can write code that a computer can understand. Good programmers write code that humans can understand.