Jacopo, Thank you a lot for your help. I will ask my questions in-line. On Sun, Oct 12, 2014 at 1:09 AM, Jacopo Cappellato <jacopo.cappell...@hotwaxmedia.com> wrote: > Hi Mansour, > > I will start with one example. > Let's say that in OFBiz we have two companies (i.e. two PartyGroup), "ABC > inc" and "CDE inc", that run two different stores selling goods to their > customers; the only way to represent that a given person "John Black" is > customer of "ABC inc", but not of "CDE inc", is using a party relationship: > "John Black is a customer of the seller ABC inc". Now suppose that John Black > is also an employee of "CDE inc"; we can represent it with another party > relationship: "John Black is an employee of the employer CDE inc". > The "party role" entity should be used to specify what are the roles that a > party can play. In our example, for John Black we would have two roles: > "customer" and "employee". > I will build on the example you gave, and model this scenario using PartyRole refrenced from PartyRelation. So we have four Roles involved. CUSTOMER SELLER EMPLOYEE EMPLOYER
John Black is a "CUSTOMER" when BUYING from the "SELLER" ABC inc. John Black is an EMPLOYEE when WORKING_FOR the "EMPLOYER" CDE inc. In this case, we don't need to define the party ids in the PartyRelationship, because the PartyRole entity has them. All we do is we reference PartyRole(s). > Summary: > * "party role": the roles that a given party *can* play > * "party relationship": the actual roles played by a given party (with > respect to other parties). > This clarifies it. But don't we find this confusing ? Why does someone get involved into a DEVELOPER relationship if she does not have the DEVELOPER PartyRole ? I mean the whole point is data integrity, by allowing only certain parties to be engaged in a specific relationship. This way we are allowing everyone to have any relationship. I hope I made my point clear. > Unfortunately in OFBiz, most of the screens and services are not implemented > considering "party relationships" but only "party roles". This simplification > is a weakness of the current implementation. > For example, a screen that lists all the "customers" doesn't make much sense > if you don't specify the company that is selling goods. Currently, if in > OFBiz a party has the role of "customer" then the system considers the party > is a customer in all the relationships. > > In my opinion we should refactor this by: > a) deprecating the party role entity > b) modify the existing code that is using party roles to use party > relationships > c) use an _NA_ party id to specify party relationship that apply to all > parties > d) in order to do #b we will need to specify, in most of the applications, > the company in which the logged in user is connected: in this way if a user > is associated to "ABC inc", in the "find customer" screen she will only see > parties that are customers of "ABC inc" > e) (optional) normalize the from/to positions in PartyRelationship by sorting > them by role type id (this would simplify lookups etc) > > I hope it is useful information and I didn't add more confusion. > > Jacopo > > On Oct 11, 2014, at 11:57 PM, Mansour Al Akeel <mansour.alak...@gmail.com> > wrote: > >> I consulted the Data Model Resource Book to refresh my memory about >> the modelling for the roles and relationship for Party. >> >> In ofbiz, we have PartyRelationship between two parties. So each party >> ID is used as a key, combined with the relationship type. The book >> mentions on page 42, that when customizing the model, it's recommended >> to draw the relationship between party roles. >> >> The part that I find confusing is, if we have the two party IDs in the >> party_role entity, why don't we create the relationship between two >> party roles, instead of duplicating the information in the >> party_relationship entity ? For example, currently we have, >> >> party_relationship: >> - from party id >> - to party id >> - from role type id >> - to role type id >> - start date >> - end date ..... >> >> Can't we just use, >> party_relationship: >> -from role >> - to role >> - party relationship type >> >> assuming John has the role of developer. IBM has the role of employer. >> We can use the directly in the party relationship. Using the current >> model, we need to add the role_type to the party_relationship. If John >> is no longer a developer, then we need to update in two entities, the >> party_relationship, and the roles. >> >> I am not sure I understand the description in the book, and the design in >> ofbiz. >> >> Can someone kindly clarify the picture for me ?? >> >> Thank you. >
