Chapter 11 Managing Object Replications

Understanding the object replication concept

In PowerDesigner you can reuse the definition of an object among several models by replicating the object in the same model or in different models.

When you replicate an object, you perform a replication that consists in creating a local copy called replica of the original object while preserving the link to it in order to automatically update the replica when the original object is modified.

An object replication is the ability to make an exact copy of an object and update this copy when the original object is modified. Attribute changes on an original object are automatically propagated to the object replica.

When you replicate an object, all its attributes are by default synchronized in the replica and appear as read-only in the replica property sheet. You can desynchronize some attributes using the Version Info page of the replica property sheet or using the replication property sheet if you want to perform a partial replication of the original object attributes and thus diverge from the original object.

For more information on how to desynchronize attributes using the Version Info page of the replica property sheet, see the "Desynchronizing replicated attributes, replicated collections and sub-replications" section.

Using object replications means you do not have to duplicate objects. The replica uses the name, code, type and Id of the target object and is automatically updated when the definition of the target object is modified.

Replica

A replica is a copy of an original object or target object. The replica references its original object in the same or in different models or packages. It owns a read-only list of synchronized attributes with those of the original object.

Referencing model

A referencing model or package is where the replica is created.

Original object

An original object is a target object that has one or more replicas in the same or in different models or packages.

Replication

A replication materializes the link between the replica and the original object. It has no symbol in the interface but does have a property sheet from which you can desynchronize replicated attributes and collections.

If you need to access the definition of a target object when it is referenced in different models, you will choose to perform an object replication and create a replica that will be an exact copy of the original object.

This local copy reuses the definition of the original object, you can access its properties even when the model that contains the original object is closed:

If you need to perform local changes on an object that references another object within the same or another model, you will choose to perform an object replication and create a replica that will allow you to diverge from the original objects attributes and customize the replica attributes according to your needs using the replication property sheet:

For more information on how to desynchronize attributes, see the "Desynchronizing replicated attributes, replicated collections and sub-replications" section.

Which objects support object replications?

You can create as many replicas as you want for most of the object types that appear under a model diagram or package in the Browser tree view.

You can also create replicas of replicas.

The following table lists objects per module that support replications:

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