Tutorials: Establishing Relationships Between Entities

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  1. On the Modeling toolbar, click the Non-Identifying, Mandatory Relationship tool.
    Notepad blue icon 2.pngNote: The screen shots of this tutorial were taken using a model where the notation was set to IE (Crow’s Feet). Depending upon the notation your model is currently set to, the icons for each relationship will be slightly different.
    Magic Wand Icon.pngTip: You can change the model notation by choosing Model > Model Options, and then selecting another notation option in the Notation area.
  2. To establish a relationship between Customer and Order, click the parent entity, Customer and then click the child entity, Order.
    Notepad blue icon 2.pngNote: ER/Studio Data Architect supports sound design practices by automatically propagating the primary key, from parent to child entities. If there are candidate alternate keys that should also be propagated to the child, in the Relationship Editor you can choose all available parent entity keys in the Parent Key list. Deleting a relationship will remove a non-native propagated attribute. However, if you want to keep the child columns of the relationship or foreign constraint, when you delete the relationship you can check the Make Foreign Keys Native option. In this case, if the relationship between Customer and Order is deleted, the CustomerID will be left in the Order entity.

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