EM0 Schema

The EM0 schema exposed by erwin DM is an extension to the M0 schema exposed by the modeling engine. The M0 schema exposes the data in a erwin DM model, including the dual objects-those objects that may exist simultaneously in both the logical and physical models.

Some of these objects may have their presence in one model or the other blocked. For example, an Entity might be marked as Is_Logical_Only. Alternatively, for historical reasons, erwin DM maintains hidden copies of an Attribute when attribute unification occurs. For example, the hidden copy of an Attribute unified on the logical side would have the Hide_In_Logical set.

This schema exposes views of these types of objects that filter out the instances that are hidden.

MV_FOREIGN_KEY_ATTRIBUTE@ can be used to help speed processing of queries. It contains rows for all foreign key attributes, joined to the following:

Entity owning the foreign key attribute
Parent attribute
Entity owning the parent attribute
Contributing relationship