When building integrations between systems, one of the first architectural choices you’ll face is how to align data between them.
Two main approaches dominate this conversation: direct field mapping and the canonical data model.
Let’s break them down.
Field Mapping: Simple but Fragile
Field mapping means you connect each field from System A directly to a matching field in System B.
It’s fast to implement and easy to visualize:
Example:
“CustomerName” → “ClientFullName”
“InvoiceDate” → “BillingDate”
Pros:
- Quick setup for simple integrations
- Easier to debug and understand
- Great for 1-to-1 integrations
Cons:
- Every new system adds complexity — you end up maintaining dozens of mappings
- Any field name or format change breaks the flow
- Hard to scale beyond a few connections
This approach is fine for small, stable environments — like syncing data between CRM and ERP once a day.
Canonical Data Model: Structured and Scalable
A canonical model introduces a shared, unified data layer — a kind of “translation dictionary” for your enterprise.
Instead of connecting systems directly, each system maps to the canonical schema.
Example:
System A → Canonical Model → System B
“CustomerName” → “Customer.FullName” → “ClientFullName”
Pros:
- Greatly simplifies multi-system integrations
- Reduces maintenance costs over time
- Makes it easier to add or replace systems
Cons:
- Requires more design work upfront
- May be overkill for small projects
- Needs governance and version control
This approach shines in large ecosystems — where data flows across multiple ERPs, CRMs, or custom apps.
So… Which One to Choose?
If you’re connecting two systems and don’t expect frequent schema changes — use field mapping.
But if your integration landscape is growing and you want to reduce long-term pain — invest in a canonical model early.
Think of field mapping as a shortcut, and the canonical model as a foundation.