Certain databases on the same server will also let you do this, if configured correctly.
For instance, if all of your databases are on the same Oracle database server, and you've granted appropriate privileges to your current user, it'll work. Mind you, this doesn't help a great deal :-) On 3/16/07, Andrus Adamchik <[EMAIL PROTECTED]> wrote:
Doing a join across DB's generally doesn't work (although it may *appear* to work in simpler cases of matching of FK), as it will require Cayenne to do in memory cartesian product processing. So you'll have to do it manually. (actually sounds like an interesting improvement ... although probably low priority to me at least) Andrus On Mar 16, 2007, at 5:26 PM, Christian Mittendorf wrote: > Hi! > > I've found the mutiple database example on cayennes homepage: > > http://cwiki.apache.org/CAY/multiple-databases-example.html > > That example is a pretty good resemblance of our current problem. > > What we would like to do is to run a single query over both > databases, like i.e. > > SelectQuery select = new SelectQuery(Person.class); > Expression expression = ExpressionFactory.matchExp > (Person.DEPARTMENT_PROPERTY + > "." + Department.NAME_PROPERTY, "IT Department"); > > But such a query runs into an exception with the following error > message: > > Base table or view not found, message from server: "Table > 'foo.bar' doesn't exist" > > Are such queries supported by Cayenne or do we have to split the > task into > two single queries? > > Christian >
