Models and Model strore in Microsoft Dynamics AX

Model were introduced in Microsoft dynamics AX 2012 to help partner and customers more easily install and maintain multiple solutions side by side in the same layers.

Model Store, is a database in which all the application elements for Microsoft dynamics ax are stored.

Models, is a set of elements in a given layer. Each layer consists of one or more models. Each layer contains one system-generated model that is specific to that layer. Every element in a layer belongs to only one model. In other words, no element can belong to two models in the same layer, and every element must belong to a model.

A default model owned by Microsoft exists in each layer. Default models cannot be modified.

Models are stored in the model store. The model store is a database in which all application elements for Microsoft dynamics ax are stored. Customizations are also stored in the model store. The model store replaces the Application Object Data (AOD) files that were used in earlier versions of Microsoft dynamics ax. Models that have been installed in the model store are used at run time.

The following table describes the scenarios in which Microsoft recommend you use each installation method.

Scenario	Recommended installation method
Distributing a solution to customers	Model files
Deploying a solution in a development or test environment	Model files or XPO files
Deploying a solution to a production environment	Model store files