On Mon, Jun 18, 2012 at 1:45 PM, Dennis Lee Bieber <wlfr...@ix.netcom.com>wrote: > > > First, is everybody on the same page (terminology)... (Independent > of Django) > > First is: multiple database engines (SQLite3, MySQL, Access/JET, > etc.). Working across multiple engines is never easy -- one typically > has to implement the equivalent of "select ... from ... join ..." in > program code -- that is, fetch records from each engine and merge them > by hand to produce a result set. > > Second is: multiple databases within an engine. Database engines are > designed to allow for separate databases with independent user access -- > a personnel/payroll database would not be accessible by the parts > order/tracking system, even when both are stored on the same database > engine/server -- however, an application /might/ be permitted such an > odd mix if the user authorization permits access to both databases. For > SQLite3 and Access/JET, a database is a single file (no particular > extension for SQLite3, Access used to use .MDB) and an application > typically opens/connects to just one of these -- but means are available > to "link" a second into visibility. > > Third: a database, as defined in #2, contains multiple relations > (tables) which may or may not be interconnected by foreign key > references (in relational database theory, a relation is a single table > in which the data of each tuple (record) is related to a unique key for > the tuple; relation does NOT refer to linkages by foreign keys between > tables).
I believe, by reading the context, it was pretty obvious he meant databases (definition #2) being managed under multiple database management systems, without regards to their specified database engine. By the way, MySQL is not a database engine -- it is a database management system. MyISAM and InnoDB would be database engines. -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
