Foreign keys in query optimization
I studied the MySQL and InnoDB manual, but I did not find anything about the internal usage of foreign keys. I mean that I would like to know if foreign keys are used for query optimizations or functions like that. Because I think foreign keys should be used not only for keeping the data integrity of the DB. Thanks, Daniel Kiss - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: Foreign keys in query optimization
Kiss Dániel wrote: I studied the MySQL and InnoDB manual, but I did not find anything about the internal usage of foreign keys. MySQL does not support foreign keys at the moment. This will be implemented in version 4.1. For more info see: http://www.mysql.com/products/mysql-4.0/index.html Cheers, Harm de Laat Informatiefabriek The Netherlands - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: Foreign keys in query optimization
If you create in index on your FK then it will be used to optimize the query. =C= * * Cal Evans * Techno-Mage * http://www.calevans.com * - Original Message - From: Kiss Dániel [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, June 10, 2002 9:19 AM Subject: Foreign keys in query optimization I studied the MySQL and InnoDB manual, but I did not find anything about the internal usage of foreign keys. I mean that I would like to know if foreign keys are used for query optimizations or functions like that. Because I think foreign keys should be used not only for keeping the data integrity of the DB. Thanks, Daniel Kiss - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
RE: Foreign keys in query optimization
InnoDB supports foreign keys. And, an index must be created on the foreign key; this would help from an optimization point of view. --Walt Weaver Bozeman, Montana -Original Message- From: harm de laat [mailto:[EMAIL PROTECTED]] Sent: Monday, June 10, 2002 8:43 AM To: Kiss Dániel Cc: [EMAIL PROTECTED] Subject: Re: Foreign keys in query optimization Kiss Dániel wrote: I studied the MySQL and InnoDB manual, but I did not find anything about the internal usage of foreign keys. MySQL does not support foreign keys at the moment. This will be implemented in version 4.1. For more info see: http://www.mysql.com/products/mysql-4.0/index.html Cheers, Harm de Laat Informatiefabriek The Netherlands - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: Foreign keys in query optimization
Kiss, Monday, June 10, 2002, 5:19:17 PM, you wrote: KD I studied the MySQL and InnoDB manual, but I did not find anything about KD the internal usage of foreign keys. KD I mean that I would like to know if foreign keys are used for query KD optimizations or functions like that. KD Because I think foreign keys should be used not only for keeping the data KD integrity of the DB. Yes, you are right. Foreign keys implement constraints or referential integrity. But you can create foreign key only on indexed column. KD Thanks, KD Daniel Kiss -- For technical support contracts, goto https://order.mysql.com/?ref=ensita This email is sponsored by Ensita.net http://www.ensita.net/ __ ___ ___ __ / |/ /_ __/ __/ __ \/ /Victoria Reznichenko / /|_/ / // /\ \/ /_/ / /__ [EMAIL PROTECTED] /_/ /_/\_, /___/\___\_\___/ MySQL AB / Ensita.net ___/ www.mysql.com - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php