Hi Riccardo, I may have completely misunderstood your intention, but here is my first cut for a model:
cayenne-o2o.xml: <?xml version="1.0" encoding="utf-8"?> <domain xmlns="http://cayenne.apache.org/schema/10/domain"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://cayenne.apache.org/schema/10/domain https://cayenne.apache.org/schema/10/domain.xsd"; project-version="10"> <map name="datamap"/> </domain> datamap.map.xml: <?xml version="1.0" encoding="utf-8"?> <data-map xmlns="http://cayenne.apache.org/schema/10/modelMap"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://cayenne.apache.org/schema/10/modelMap https://cayenne.apache.org/schema/10/modelMap.xsd"; project-version="10"> <property name="defaultLockType" value="1"/> <property name="defaultPackage" value="org.test"/> <db-entity name="SHIPMENT"> <db-attribute name="ID" type="BIGINT" isPrimaryKey="true" isMandatory="true" /> </db-entity> <db-entity name="SHIPMENT_NUMBER"> <db-attribute name="ID" type="BIGINT" isPrimaryKey="true" isMandatory="true" > <info:property xmlns:info="http://cayenne.apache.org/schema/10/info"; name= "comment" value="This ID is the same as SHIPMENT's ID."/> </db-attribute> <db-attribute name="NUM" type="INTEGER"> <info:property xmlns:info="http://cayenne.apache.org/schema/10/info"; name= "comment" value="This is the shipment number."/> </db-attribute> </db-entity> <obj-entity name="Shipment" className="org.test.Shipment" lock-type= "optimistic" dbEntityName="SHIPMENT"/> <obj-entity name="ShipmentNumber" className="org.test.ShipmentNumber" lock-type="optimistic" dbEntityName="SHIPMENT_NUMBER"> <obj-attribute name="num" type="java.lang.Integer" db-attribute-path="NUM"/> </obj-entity> <db-relationship name="toShipNum" source="SHIPMENT" target="SHIPMENT_NUMBER" > <db-attribute-pair source="ID" target="ID"/> </db-relationship> <db-relationship name="toShip" source="SHIPMENT_NUMBER" target="SHIPMENT" toDependentPK="true"> <db-attribute-pair source="ID" target="ID"/> </db-relationship> <obj-relationship name="toShipNum" source="Shipment" target="ShipmentNumber" deleteRule="Cascade" db-relationship-path="toShipNum"/> <obj-relationship name="toShip" source="ShipmentNumber" target="Shipment" deleteRule="Deny" db-relationship-path="toShip"/> </data-map> Copy/Paste these files somewhere, then try loading them up into your 4.2 Modeler and see if it is close. mrg On Tue, Jan 9, 2024 at 9:54 AM Riccardo De Menna <deme...@tuorlo.net> wrote: > Hi, > > Can someone help me understand something? > > I’m trying to model a one-to-one relationship between two entities but I > can’t seem to get the relationship to be optional. > > In my specific case I need to model an entity representing shipments with > a postal service. Each shipment needs to have a number taken from a > range/group that is pre-assigned by the postal service. > > Thus I created a SHIPMENT_NUMBER entity with just an INTEGER attribute and > then used that attribute to build the relationship with the SHIPMENT > entity. Possibly with “To dep PK” as well. > > I want the relationship to be optional so that I can generate > SHIPMENT_NUMBER as many as I want and populate them with the numbers > assigned by the postal service and only later, when the real SHIPMENT is > actually needed/created, link it with the number in a one-to-one fashion. > > I’m not sure why, but my class generated content always shows the > relationship as mandatory. > > Coming from the WebObjects world, I'm used to a modeler that explicitly > shows checkboxes for isMandatory on relationships like with the attributes. > Here in Cayenne it seems that optionality is implicitly determined based on > the design. > > Have I misunderstood something? Is my design flawed? > > Any tip is appreciated. > > Regards, > Riccardo
