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Automatically Resolving Conflicting Definitions

You can direct G2 to resolve most conflicts among definitions of classes automatically. This ability is sometimes referred to as automerge.

To resolve conflicts automatically when merging KBs:

Select the automatically resolve conflicts option in the Load KB dialog when you use it to merge in a KB.

When merging KBs, or when loading modularized KBs with the automatically resolve conflicts option selected, G2 checks each pair of conflicting definitions to see whether they can be merged automatically.

Two definitions of the same type can be automerged if they have the same foundation classes OR no instances of the secondary definition exist.
An OBJECT-DEFINITION, CONNECTION-DEFINITION, or MESSAGE-DEFINITION can be automerged into a CLASS-DEFINITION if they have the same foundation classes OR no instances of the secondary definition exist.
A CLASS-DEFINITION cannot be automerged into an OBJECT-DEFINITION, CONNECTION-DEFINITION, or MESSAGE-DEFINITION, even if they have the same foundation classes.

When G2 automerges two KBs, it does the following for each pair of definitions that can be merged automatically:

For each attribute that differs, G2 performs a change the text of action to change the attribute in the secondary definition to be equivalent to its corresponding attribute in the primary definition.
In the secondary definition item, G2 opens the Change attribute and executes:
After G2 automerges two definitions, it deletes the secondary definition.

Automerging an OBJECT-DEFINITION, CONNECTION-DEFINITION, or MESSAGE-DEFINITION into a CLASS-DEFINITION cannot be done by directly transferring attributes, because the syntax differs in the two types of definition. G2 carries out such a merge by changing the syntax of the information in the secondary definition as needed to fit into a CLASS-DEFINITION.

Automerging two definitions resolves every difference between the primary and secondary definitions in favor of the primary definition:

Attributes defined in the secondary definition but not the primary definition disappear from subclasses and instances of the secondary definition.
Attributes defined in the primary definition but not the secondary definition are added to subclasses and instances of the secondary definition.
Attributes that exist in both definitions but have different properties use the properties in the primary definition. Subclasses and instances of the secondary definition change accordingly.

If all conflicting definitions can be merged automatically, the KBs themselves have been successfully automerged. If any pair of definitions cannot be automerged, G2 treats them as it does all conflicting definitions during an ordinary merge, as described in the next section.

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