My databases textbook from college says that specifying an attribute as an "index" means that the data will be stored in such a way that lookups on that attribute are faster, and specifying an attribute as a "key" means that its values have to be unique.
But MySQL seems to use KEY and INDEX to mean the same thing (e.g. http://www.mysql.com/doc/C/R/CREATE_TABLE.html -- "KEY is a synonym for INDEX" -- and http://www.mysql.com/doc/S/H/SHOW_DATABASE_INFO.html , which lists some more commands where the two are used interchangeably). In both cases, they mean what my textbook refers to as an index, and MySQL uses "unique key" to mean what my textbook calls a key. What are the *standard* meanings of these terms? The usage in the textbook makes more sense (and seems to be the terminology used by MS Access as well); how did MySQL end up using them differently? -Bennett [EMAIL PROTECTED] http://www.peacefire.org (425) 649 9024 --------------------------------------------------------------------- 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
