Lesson 6 — Identifiers, Relationships, and Master Data Domains
Once records are reconciled, the enterprise needs a stable way to identify the entity while preserving traceability back to local systems. It also needs to represent relationships among entities without forcing every relationship into one hierarchy.
Source ID
A Source ID is the identifier assigned by an individual source system.
Examples:
- CRM customer 381
- Billing customer 99
- Service customer C-44
These identifiers can remain useful locally. MDM does not require erasing them.
Global ID
A Global ID is the enterprise identifier assigned and maintained for a reconciled master entity.
If the three source records above are confirmed to represent one customer, the MDM environment might assign enterprise ID G-100.
Only one authorized solution should generate Global IDs so the enterprise does not create competing or colliding identities.
X-Ref
X-Ref is the mapping and history between local Source IDs and the Global ID.
It answers:
Which local records have represented this enterprise identity, and how has that mapping changed over time?
X-Ref is not “another ID.” It is the translation/traceability layer.
Identifier picture
CRM 381 ─┐
Billing 99 ─┼─ X-REF HISTORY → Global ID G-100
Service C-44 ─┘
If an incorrect merge is later undone, the history must preserve which source IDs move to which corrected Global IDs.
Do not confuse Master X-Ref with Reference cross-reference
A Reference cross-reference maps equivalent code representations such as US ↔ USA ↔ 840.
A Master Data X-Ref maps source entity identifiers to one enterprise entity identity.
Both are mappings, but they solve different problems.
Identity management vs affiliation management
Identity management answers: Who/what is this entity, and which stable identifier represents it?
Affiliation management answers: How are entities related?
Examples of affiliations: - subsidiary-of; - works-at; - member-of; - household relationship; - supplier-for; - legal or business association.
Affiliations are useful when relationships are typed, flexible, many-to-many, or need different views.
Affiliation vs parent-child
A parent-child relationship is a direct hierarchy. It is appropriate when the business truly needs one hierarchical navigation structure.
Affiliation is more flexible. A person can work for more than one organization; a company can participate in several networks; a location can serve multiple relationships.
The exam clue is whether the relationship is a fixed hierarchy or a flexible typed association.
Common Master Data domains
Party
People and organizations in roles such as customer, supplier, employee, or partner.
Financial
Charts of accounts, cost centers, financial structures, or similar persistent financial context.
Legal
Legal entities and relationships.
Product
Products/services and their persistent attributes. Product classifications may rely on Reference Data.
Location
Specific enterprise locations, facilities, addresses, or geographic coordinates. Do not confuse a particular location entity with geographic code Reference Data.
Industry directories and other enterprise domains
The exact domain list depends on the business. What matters is persistent identity reused across processes.
Stop and check
US= Reference value.- Distribution Center 17 at a particular address = Location Master Data.
- CRM ID
381= Source ID. - Enterprise Party
G-100= Global ID. - mapping
381 → G-100= X-Ref.
Source anchor: pp. 346–349.