IBM BPM, V8.0.1, All platforms > Authoring services in Integration Designer > Developing monitor models > Create monitor models > Combining or merging monitor models
When to use combine versus merge
When you combine or merge two models, you end up with a single monitor model, reducing the work required for separate management and deployment.
Combine models when they are unrelated. Merge them when they are different versions of the same model or when one is a copy of the other.
Combining monitor models is easier than merging monitor models. When you merge models, each change in each model (monitor details model, dimensional model, KPI model, event model, and visual model) must be dealt with individually. If you are merging monitor models in which the IDs assigned to the top-level monitoring contexts, KPI contexts, and so on are distinct, this task can become tedious and error-prone. However, you might want to merge models if you are comparing two monitor models that are branches of a common ancestor and hence share a number of monitoring elements. Individual changes between various aspects of these models can then be identified and dealt with accordingly.
The main difference between combining and merging models is the way that the two operations treat matching IDs. If you have two models, each of which has a monitoring context called A1, the following table shows the result:
Operation Result Combine Two monitoring contexts, called A1 and A1_1 Merge A single monitoring context called A1 containing elements from both the contexts Merging models identifies elements with matching IDs as being the same and looks for differences within the elements, whereas combining models maintains a distinction between the elements, and modifies (using model refactoring) the ID of one of the duplicate elements before combining the results into the target model. The target model still contains a distinct representation for each of the top-level elements if they are combined, but only one representation if they are merged.