eclipse-viatra-bot
commented
6 months ago By Gabor Bergmann on Mar 20, 2020 08:32
Thanks for the report. I agree that there could be more explanation to help the user.
In the context below, the pattern identifies all employees and all contractors, but no connection between them. If there are 1000 employees and 1000 contractors, it will return one million employee-contractor pairs. This is probably not what you want.
For all users, it should hold that they can either have the "Employee" role or the "Contractor" role but not both.
This is not what your pattern expresses though! A violation of your rule would entail a single user having both roles. So the pattern should read userE==userC instead of userE!=userC to express this.
In this case, the warning might have helped you catch a bug in your pattern code.
| --- | --- | | Bugzilla Link | 561297 | | Status | NEW | | Importance | P3 normal | | Reported | Mar 20, 2020 08:25 EDT | | Modified | Mar 30, 2020 11:19 EDT | | Reporter | Hans van der Laan |
Description
While trying to make some patterns, I got the following error message:
The pattern body contains constraints which are only loosely\ connected. This may negatively impact performance. The weakly\ dependent partitions are: [userE, employee][userC, contractor]
I do not know what "loosly connected" constraints are. There is no mention of what exactly are loosly connected constraints in the Query Language documentation. It would be useful if this was added to the documentation.
This looks like an error message I got previously about "isolated" constraints. There is also no mention of isolated constraints in the documentation. However, from the error message I think I understood what this meant.
For context, I was trying to model a mutual exclusion pattern. I have a model where users are assigned roles. For all users, it should hold that they can either have the "Employee" role or the "Contractor" role but not both.
pattern SoDEmployeeAndContractor(userE: User, userC: User, employee : Role, contractor : Role) {\ Role.name(employee, "Employee");\ Role.name(contractor, "Contractor");\ Role.RU(employee, userE);\ Role.RU(contractor, userC);\ userE!=userC;\ }