Interactive Pattern

Historical Conformance

Historical Conformance aligns multiple source histories into one consistent reporting view when systems disagree over time.

Problem

Two source systems describe the same customer differently.

Historical reporting often combines CRM, policy, billing or product systems. Each system may have its own version of customer segment, product category, broker assignment or risk classification.

If the model does not define conformance rules, the same business entity can appear with different historical attributes in the same reporting period.

Cross-system conflictsDifferent historical truthsUnclear source ownershipInconsistent reporting attributes

Example

CRM and policy system disagree about the customer segment for the same reporting period.

System A

CRM

Retail

Source says customer is Retail

System B

Policy System

Private

Source says customer is Private

Reporting question

Which customer segment should the March snapshot use when systems disagree about the same customer and period?

✓

Expected Result (Conformed)

System A

conformed

Retail

System B

conformed

Retail

Common Wrong Result (Risk)

System A

unconformed

Retail

System B

unconformed

Private

Key idea

A conformed model makes the rule explicit. Either the conflict is resolved to one reporting value or it is clearly marked as unresolved.

Test case

Try this Historical Conformance case in Target Table Validation

Use these sample target tables to test the validator:

Copy one of the target tables below.
Open Target Table Validation.
Paste the copied table as your target output.
Check whether the result is conformed or still conflicting.

Conformed target table

Copy this table to validate the expected conformed reporting output.

contract_id,customer_key,source_system,customer_segment,conformance_status,snapshot_date,valid_from,valid_to
C-1001,Customer A,System A,Retail,conformed,2024-03-31,2024-03-01,2024-03-31
C-1001,Customer A,System B,Retail,conformed,2024-03-31,2024-03-01,2024-03-31

Wrong target table

Copy this table to validate a risky output where cross-system conflicts remain unresolved.

contract_id,customer_key,source_system,customer_segment,conformance_status,snapshot_date,valid_from,valid_to
C-1001,Customer A,System A,Retail,unconformed,2024-03-31,2024-03-01,2024-03-31
C-1001,Customer A,System B,Private,unconformed,2024-03-31,2024-03-01,2024-03-31

Open Target Table Validation →

Key idea

Conformance turns source-specific history into reporting history.

A conformed historical model does not simply copy every source value. It defines which source owns each attribute, how conflicts are resolved and which values are safe to use in reporting.

Why it happens

Each source system optimizes for its own operational process.

CRM vs ERP mismatchMaster data correctionsLate arriving source updatesDifferent effective datesSource-specific code systems

Typical solutions

Make source ownership and conflict handling explicit.

Source Ownership Rules

Define which system owns each historical attribute when sources disagree.

Conformed Dimensions

Standardize historical attributes into one reporting vocabulary.

Conflict Status

Explicitly mark unresolved differences instead of silently choosing one source.

As-Known Conformance

Preserve when conflicting source history became visible to reporting.

Validation checks

Validate whether the conformed history is safe for reporting.

✓ Cross-system attribute consistency✓ Conformance status validation✓ Source ownership validation✓ Historical conflict detection✓ Snapshot conformance validation

Why it matters

Without conformance, different systems can produce different historical truths.

Historical Conformance is often the difference between a collection of historized source tables and a trustworthy reporting model.

Related Patterns

State ↔ State Alignment Dimension Completion Rectangle Decomposition Snapshot Reproducibility Relationship History

Try it

Review your own historical conformance rules.

Use the Historical Modeling Workbench to reason about source ownership, conformed dimensions and cross-system historical conflicts.

Review My Model →