Hi Richard,
Can you make a relationship between COMPOSITIONS and INSTALATIONS? If so, then you make a relationship between COMPSOTIONS_ONSTALATIONS and PERFORMANCES. Laercio. -----Original Message----- From: Richard Lewis [mailto:[EMAIL PROTECTED] On Behalf Of Richard Lewis Sent: terça-feira, 25 de maio de 2004 09:58 To: [EMAIL PROTECTED] Subject: Relationships Question Dear List, I am working on a database of electronic compositions (and installations etc.) and currently have, amongst others, the following tables: ARTIST(_id_,...) SCORE(_id_,_artist_id_,...) COMPOSITIONS(_id_,_score_id_,...) INSTALLATIONS(_id_,_score_id_,...) PERFORMANCES(_id_,???) The PERFORMANCES table lists dates and locations (etc.) of performances of COMPOSITIONS and INSTALLATIONS in the database. My current entity relationship diagram gives a one-to-many relationship between COMPOSITIONS and PERFORMANCES and between INSTALLATIONS and PERFORMANCES. However, this would involve PERFORMANCES having two foriegn keys (composition_id and installation_id) one of which would be redundant. Whats the best way to design this relationship? Cheers, Richard -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
