Hi, On Wed, Apr 2, 2008 at 4:34 PM, Ben Roberts <[EMAIL PROTECTED]> wrote: > > Hello, > > Does anybody have any info on cross-database joins? > > i.e. doing a join across various tables that are located inside different > databases (albeit on the same database server). > > I'm interesested in any potential pitfalls, limitations, and performance > issues. There doesn't appear to be much information about this on the web > (at least not that I can find so far).
There are sometimes queries that are hard to write so MySQL doesn't complain about an error, but this is not hard to avoid: http://www.xaprb.com/blog/2006/08/07/how-to-write-multi-table-cross-database-deletes-with-aliases-in-mysql/ > I'm using the InnoDB engine. Do foreign key constraints work across > different databases too? FK constrraints work fine across databases. Regards Baron -- Baron Schwartz, Senior Consultant, Percona Inc. Tel: +1 888 401 3401 ext 507 24/7 Emergency Line +1 888 401 3401 ext 911 Our Services: http://www.percona.com/services.html Our Blog: http://www.mysqlperformanceblog.com/ -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
