Hi Alexej Thanks a lot for your explanations.
Your ASCII-Art was very helpful to understand what is going on in terms of *graphs*. But I still have not completely understood what are the real consequences of the different graphs when it comes to the concrete data-modelling in a real application. Could we take again the concrete example of the Resource Graph ACTOR.E39: The mergenodes there are: PLACE.E53, APPELATION.E41 and ARCHES_EVENT_PHASE.E4 END_OF_EXISTENCE.E64 e.g. is NOT a merge node. As END_OF_EXISTENCE.E64 e.g. is NOT a merge node, it's child nodes (e.g. END_OF_EXISTING_TYPE and END_DATE_OF_EXISTENCE) would end up in separate sub-trees directly attached to the root node? Or they doen't because they always are entered together in one input form. and the code there makes sure that END_TYPE and END_DATE become not separated? But then again, if this would have to be taken care of in the code anyway, what would be the role of the mergenode? Also: I cannot "see" any difference for those sub-trees *with* mergenodes (e.g. APPELATION) and those *without* (e.g. END_OF_EXISTENCE) in the surface-behaviour of arches-hip: they don't behave differently in the input forms (I can add multiple NAMES and multiple birth-dates to a person)? The system itself will allow you to save any shape graph you want (correct > or otherwise). It's up to you as a developer to understand the intent of > the graph shape and then use the mergenode information to achieve that goal. So do you mean, that the merge-node information is not used by the (current) system at all, and that it is only there to *inform* the programmer of the data-modeller's "intention"??? all the best Hannes Am Dienstag, 14. Juli 2015 11:53:15 UTC+2 schrieb H Pirker: > > Dear all, > > Can somebody comment on the role & purpose of "mergenode" in Resource > Graphs. > > In the documentation ( > http://arches3.readthedocs.org/en/latest/arches-data/#resource-graphs ) > it just says: > > mergenode: defines the upstream node that occurs one time (and only one >> time) within a given resource instance. In most cases, that node is the one >> that represents the resource itself. > > > When inspecting an existing graph. e.g. ACTOR.E39 I can see that the > mergenode depicts the root of "useful" sub-graphs, i.e. for PLACE, > APPELATION and ARCHES_EVENT_PHASE. > > But what are actually the consequences of adding mergenodes - or leaving > them out? Is it used and/or required for specifiying "required" and > "unique" (""one time (and only one time)" ) ? (But this would mean, that > only a SINGLE ARCHES_EVENT_PHASE can be assigned to a ACTOR, which seems > odd ?) > Why do some sub-graphs have a mergenode, while others just "merge" with > the root-node of the whole Resource Graph ? (e.g. > BEGINNING_OF_EXISTENCE_TYPE.E63) > > yours puzzled :-) > > Hannes > > -- -- To post, send email to [email protected]. To unsubscribe, send email to [email protected]. For more information, visit https://groups.google.com/d/forum/archesproject?hl=en --- You received this message because you are subscribed to the Google Groups "Arches Project" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
