Hello Graphistas

I just had to learn the hard way that SDG does not allow having two relationships of the same type between the same two nodes. Is there any compelling reason why this restriction has been introduced? It makes the representation of our model unnecessarily hard.

In our domain, we model data flows between objects. A user can create different flow models where he can put different objects and connects them with flow relationships. I.e.:

Flow model 1 defines the flow:

a --> b --> c

Flow model 2 defines the flow:

a --> b --> x --> c

The resulting graph could be e.g.:

https://chart.googleapis.com/chart?c...22fmId=f2%22]}

In this graph model, there are now two "flows_to" relationships between the nodes a and b, once for the flow model 1 and once for the flow model 2. Our approach was to add the id of the flow model as a property "flowModelId" (fmId in the graph above) to the "flows_to" relationship. To recreate the flow in flow model 1, we'd traverse all flow_to relationships that have the "flowModelId" set to the appropriate flow model. This is a valid reason, having two relationships of the same type between the same two nodes, isn't it?

Any chance to remove this restriction?

Best regards,

James

I just had to learn the hard way that SDG does not allow having two relationships of the same type between the same two nodes. Is there any compelling reason why this restriction has been introduced? It makes the representation of our model unnecessarily hard.

In our domain, we model data flows between objects. A user can create different flow models where he can put different objects and connects them with flow relationships. I.e.:

Flow model 1 defines the flow:

a --> b --> c

Flow model 2 defines the flow:

a --> b --> x --> c

The resulting graph could be e.g.:

https://chart.googleapis.com/chart?c...22fmId=f2%22]}

In this graph model, there are now two "flows_to" relationships between the nodes a and b, once for the flow model 1 and once for the flow model 2. Our approach was to add the id of the flow model as a property "flowModelId" (fmId in the graph above) to the "flows_to" relationship. To recreate the flow in flow model 1, we'd traverse all flow_to relationships that have the "flowModelId" set to the appropriate flow model. This is a valid reason, having two relationships of the same type between the same two nodes, isn't it?

Any chance to remove this restriction?

Best regards,

James

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