System of Record vs. External ID Sync Modes

When configuring data synchronization between two systems, you can choose between two primary sync modes: System of Record and External ID. Both modes support bidirectional sync, but differ in how records are matched and how identifiers are managed.

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System of Record (SOR) Mode

• Identifiers Used:

  • The primary key of the System of Record (SOR) is the unique identifier for matching records.
  • An additional field in both systems acts as the "external ID" to track the SOR primary key.

• How it Works:

  • Record Created in SOR:
    • The record is synced to the other system.
    • The external ID field in the non-SOR system is set to the value of the SOR's primary key.
  • Record Created in Non-SOR:
    • The record is synced to the SOR, which generates a primary key.
    • The external ID field in the non-SOR system is updated to match the new SOR primary key.
  • Updates:
    • Updates in either system are matched using the SOR primary key (via the external ID field in the non-SOR system).
    • Changes are propagated bidirectionally, always referencing the SOR primary key.
  • Deletes:
    • Deletions are matched and propagated using the SOR primary key and the external ID field.

• Use Case:

  • Use SOR mode when you want one system to be the authoritative source for record identity, but still allow bidirectional updates.

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External ID Mode

• Identifiers Used:

  • Both systems must have an "external ID" field.
  • The external ID is the unique identifier for matching records across systems.

• How it Works:

  • Record Created:
    • If a record is created in either system and has an external ID value, it is synced to the other system using that external ID.
    • If a record is created without an external ID, it is not synced until the external ID is set.
  • Updates:
    • Updates are matched and synced using the external ID field in both systems.
  • Deletes:
    • Deletions are matched and propagated using the external ID.

• Use Case:

  • Use External ID mode when records may originate in either system and you want a shared, user-defined identifier to link records.

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Summary Table