From: Eric W. <eri...@gm...> - 2007-10-25 18:24:05
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No problem. Let's say I want to insert the following document into eXist: <Alarm> <ProcessId>7</ProcessId> <ActivityId>17</ActivityId> <Deadline>2008-12-10T12:30:00Z</Deadline> </Alarm> I can insert that content and everything is fine. If I then try to insert another instance of <Alarm> that has the same ProcessId and ActivityId, I would like eXist to fail on the insert. In other words, I want to configure a unique constraint for the given two xpaths: /Alarm/ProcessId /Alarm/ActivityId Much like you would have in SQL for a unique key or primary key. Another example is Tamino - which allows for the creation of xpath-defined unique constraints in a doctype. In the normal course of operation, our software will not try to insert two documents that are the same. However, recently we found a defect during our application crash recovery code, where we had a bug that caused a duplicate Alarm document to be inserted. When running against SQL, this bug was obvious (because it failed fast with a UNIQUE KEY CONSTRAINT VIOLATION sql error). When running against eXist, there was obviously no error. So I'm wondering if eXist already has a feature like this, or will I need to add a custom layer within or on top of eXist. Thanks, - Eric Dannes Wessels wrote: > Eric > > On 10/25/07, Eric Wittmann <eri...@gm...> wrote: >> Is there any way to specify a uniqueness constraint? > > in what respect is this an eXist specific question? Please make your > question a bit longer :-) > |