# Golden records with duplicate rules and merge

*Platform Data Architect Study Guide · Master Data Management · Last updated October 26, 2026 · https://www.certifyforce.com/study-guide/platform-data-architect/master-data-management/golden-records-with-duplicate-rules-and-merge*

How to make one trusted customer record in a single org: name the system of record per entity, stop new duplicates with matching and duplicate rules, find old ones with duplicate jobs, and merge them knowing what the principal record, related records, Chatter, files and contact points do.

- Certification: Salesforce Platform Data Architect
- Exam section: Master Data Management
- Study guide: https://www.certifyforce.com/study-guide/platform-data-architect

**Official exam objective:**

> Given a customer scenario, recommend and use techniques for establishing a "golden record" or "system of truth" for the customer domain in a single org.

## What the exam expects

- Name the system of record for each customer entity and fields before building a golden record in one org.
- Combine matching rules and duplicate rules (alert, block, report) to stop new duplicates, and know their limits.
- Clean existing duplicates with duplicate jobs and merges, choosing the principal record deliberately.
- Predict what a merge does to hidden fields, related records, Chatter, files and contact points, in the UI and in Apex.

Key terms: **golden record** (one best value per attribute, which MDM writes back); **system of record** (the system that owns an entity's data); **matching rule** (how potential duplicates are identified); **duplicate rule** (what happens when one is found); **principal record** (the merge survivor whose hidden and read-only values are kept).

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Duplicate rule actions | Alert, block or report; defaults alert and report | [Customize Duplicate Rules](https://help.salesforce.com/s/articleView?id=sales.duplicate_rules_create.htm&type=5) |
| Rule limits | 5 active duplicate rules per object; 3 matching rules per duplicate rule | [Duplicate Rules](https://help.salesforce.com/s/articleView?language=en_US&id=sales.duplicate_rules_overview.htm&type=5) |
| Manual merge | Duplicate rules don't run | [Duplicate Rules](https://help.salesforce.com/s/articleView?language=en_US&id=sales.duplicate_rules_overview.htm&type=5) |
| Duplicate jobs | Performance and Unlimited; Customize Application and View All Data | [Duplicate Jobs](https://help.salesforce.com/s/articleView?id=sales.duplicate_jobs.htm&type=5) |
| Merge size | Up to three records at a time | [Merge in Lightning](https://help.salesforce.com/s/articleView?language=en_US&id=sales.account_merge_lex.htm&type=5) |
| Hidden and read-only fields | Kept from the principal record | [Merge Considerations](https://help.salesforce.com/s/articleView?id=sales.account_merge_considerations.htm&language=en_US&type=5) |
| Chatter and files | Feeds from the principal only; files kept | [Merge Considerations](https://help.salesforce.com/s/articleView?id=sales.account_merge_considerations.htm&language=en_US&type=5) |
| Contact points | Relationships to person accounts lost on merge | [Merge Considerations](https://help.salesforce.com/s/articleView?id=sales.account_merge_considerations.htm&language=en_US&type=5) |
| Apex merge | Deletes duplicates and reparents related records | [Merging Records](https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/langCon_apex_dml_examples_merge.htm) |

## Check yourself

- Why should the record an integration maintains usually be the principal?
- When does a duplicate rule not run even though it is active?
- What happens to a duplicate account's contacts when Apex merges it into a main account?
- Which two permissions does a user need to run duplicate jobs?

## Sources

- [Considerations for Merging Duplicate Accounts](https://help.salesforce.com/s/articleView?id=sales.account_merge_considerations.htm&language=en_US&type=5)
- [Merge Duplicate Accounts in Lightning Experience](https://help.salesforce.com/s/articleView?language=en_US&id=sales.account_merge_lex.htm&type=5)
- [Things to Know About Duplicate Rules](https://help.salesforce.com/s/articleView?language=en_US&id=sales.duplicate_rules_overview.htm&type=5)
- [Customize Duplicate Rules](https://help.salesforce.com/s/articleView?id=sales.duplicate_rules_create.htm&type=5)
- [Manage Duplicate Records](https://help.salesforce.com/s/articleView?id=sales.managing_duplicates_overview.htm&language=en_US&type=5)
- [Find Duplicates Across Your Org Using Duplicate Jobs](https://help.salesforce.com/s/articleView?id=sales.duplicate_jobs.htm&type=5)
- [Resolve and Prevent Duplicate Data in Salesforce](https://trailhead.salesforce.com/content/learn/modules/sales_admin_duplicate_management/sales_admin_duplicate_management_unit_2)
- [Stop Users from Creating Duplicate Records](https://help.salesforce.com/s/articleView?id=sales.duplicate_prevention.htm&language=en_US&type=5)
- [Considerations for Using Person Accounts](https://help.salesforce.com/s/articleView?id=sf.account_person_behavior.htm&language=en_US&type=5)
- [Merging Records](https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/langCon_apex_dml_examples_merge.htm)
- [Understand Unified Profiles and Their Impacts on Data Strategy](https://trailhead.salesforce.com/content/learn/modules/data-and-identity-in-salesforce-cdp/get-to-know-unified-profiles)
- [Designing Enterprise Data Architecture on the Salesforce1 Platform](https://developer.salesforce.com/blogs/developer-relations/2014/11/enterprise-data-architecture)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 8 linked practice questions, and unlimited timed mock exams are included with the Platform Data Architect pack (USD $19): https://www.certifyforce.com/practice-exams