On Fri, 6 Aug 2004 16:26:53 +0300, DebugasRu <[EMAIL PROTECTED]> wrote: > > since SQL89 standard lot of things got standartized but still there > are more things to unify. One of them is metadata (system tables that > a given DBMS uses) processing. I want to ask if there is going to be any standard on > that ? Namely any unified way (for different DBMSs) to extract and > modify metadata about the user database - primary keys, foreign keys, info on > cascade updates/deletes settings, default values, ranges of allowed values and so on.
That standard already exists, MySQL just doesn't implement it. The SQL standard defines form and function of a so-called INFORMATION_SCHEMA in which various views reside that contain said information. For instance, primary keys and foreign keys would be identified by the CONSTRAINT_TYPE field of the INFORMATION_SCHEMA.TABLE_CONSTRAINTS view. Actions on delete and update would be in the UPDATE_RULE and DELETE_RULE fields of the INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS view. Etc. etc. etc. If you are interested you can probably find a lot more documentation in the PostgreSQL manual or you can buy a copy of ISO/IEC 9075-11:2003. But don't hold your breath, judging by the roadmap none of it will work in MySQL for quite some years. Jochem -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
