# Data migration, quality and large data volumes

*Agentforce Service Consultant Study Guide · Implementation Strategies · Last updated October 15, 2026 · https://www.certifyforce.com/study-guide/agentforce-service-consultant/implementation-strategies/data-migration-quality-and-large-data-volumes*

Plan a service data migration (load order, External IDs, Bulk API, full-sandbox rehearsal, lean loading and deferred sharing), avoid ownership and lookup skew, keep millions of cases fast with selective queries and archiving, and protect quality and sensitive data with duplicate rules and governance.

- Certification: Salesforce Agentforce Service Consultant
- Exam section: Implementation Strategies
- Study guide: https://www.certifyforce.com/study-guide/agentforce-service-consultant

**Official exam objective:**

> Explain the considerations and implications for data migration, data quality, data governance, and large data volumes.

## What the exam expects

- Sequence a service data migration, relate records with External IDs, and pick the load tool by volume.
- Speed up large loads: Bulk API, parallel versus serial, suspending automation, deferring sharing calculations.
- Recognize ownership skew, account data skew and lookup skew, and fix each.
- Keep large case volumes fast with selective, indexed filters, reporting snapshots and archiving.
- Protect data quality (cleansing, duplicate and matching rules) and set up governance and sensitive-data handling.

Key terms: **LDV** (large data volumes: millions of records); **data skew** (more than 10,000 child records on one parent); **External ID** (a field holding the record's key from another system); **selective query** (a filter on an indexed field that returns a small share of rows); **data steward** (the person responsible for data quality).

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Load order | Parents first, then children; order by parent ID to avoid locking | [Manage Data at Scale](https://trailhead.salesforce.com/content/learn/modules/scalability-with-salesforce/manage-data-at-scale-with-salesforce) |
| Tool by volume | Import Wizard up to 50,000; Data Loader 50,000 to 5 million; LDV via Bulk API | [Manage Data at Scale](https://trailhead.salesforce.com/content/learn/modules/scalability-with-salesforce/manage-data-at-scale-with-salesforce) |
| External IDs | Up to 25 per object; used to update or upsert via the API | [Custom Field Attributes](https://help.salesforce.com/s/articleView?id=sf.custom_field_attributes.htm&type=5) |
| Bulk API batch | Up to 10,000 records; parallel or serial | [Load Your Data](https://trailhead.salesforce.com/content/learn/modules/large-data-volumes/load-your-data) |
| Defer sharing | Off by default; enable via Customer Support; resume and fully recalculate | [Defer Sharing Calculations](https://help.salesforce.com/s/articleView?id=sf.security_sharing_defer_sharing_calculations.htm&language=en_US&type=5) |
| Data skew threshold | More than 10,000 children on one parent | [Design Your Data Model](https://trailhead.salesforce.com/content/learn/modules/large-data-volumes/design-your-data-model) |
| Unavoidable ownership skew | Give the skewed owner no role | [Design Your Data Model](https://trailhead.salesforce.com/content/learn/modules/large-data-volumes/design-your-data-model) |
| Big Objects | Can't be modified after insert | [Resource and Cost Optimization](https://architect.salesforce.com/docs/architect/well-architected/guide/resource-and-cost-optimization.html) |
| Duplicate rules | Alert or block; standard rules active for accounts, contacts, leads | [Stop Users from Creating Duplicate Records](https://help.salesforce.com/s/articleView?id=sales.duplicate_prevention.htm&language=en_US&type=5) |
| Reporting snapshot | Schedules report results into a custom object for trends | [Reporting Snapshots](https://help.salesforce.com/s/articleView?id=analytics.data_about_analytic_snap.htm&language=en_US&type=5) |

## Check yourself

- Why load accounts before cases?
- When should a consultant request a custom index?
- What does an External ID field let a migration do?
- Which two stewardship roles support a governance plan?

## Sources

- [Manage Data at Scale with Salesforce](https://trailhead.salesforce.com/content/learn/modules/scalability-with-salesforce/manage-data-at-scale-with-salesforce)
- [Load Your Data (Large Data Volumes)](https://trailhead.salesforce.com/content/learn/modules/large-data-volumes/load-your-data)
- [Design Your Data Model (Large Data Volumes)](https://trailhead.salesforce.com/content/learn/modules/large-data-volumes/design-your-data-model)
- [Conduct Data Queries and Searches](https://trailhead.salesforce.com/content/learn/modules/large-data-volumes/conduct-data-queries-and-searches)
- [Defer Sharing Calculations](https://help.salesforce.com/s/articleView?id=sf.security_sharing_defer_sharing_calculations.htm&language=en_US&type=5)
- [Custom Field Attributes](https://help.salesforce.com/s/articleView?id=sf.custom_field_attributes.htm&type=5)
- [Resource and Cost Optimization](https://architect.salesforce.com/docs/architect/well-architected/guide/resource-and-cost-optimization.html)
- [Stop Users from Creating Duplicate Records](https://help.salesforce.com/s/articleView?id=sales.duplicate_prevention.htm&language=en_US&type=5)
- [Report on Historical Data with Reporting Snapshots](https://help.salesforce.com/s/articleView?id=analytics.data_about_analytic_snap.htm&language=en_US&type=5)
- [Govern and Secure (Data 360)](https://help.salesforce.com/s/articleView?id=data.c360_a_data_governance.htm&language=en_US&type=5)
- [Insert, Update, or Delete Data Using Data Loader](https://developer.salesforce.com/docs/atlas.en-us.dataLoader.meta/dataLoader/inserting_updating_or_deleting_data.htm)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 14 linked practice questions, and unlimited timed mock exams are included with the Agentforce Service Consultant pack (USD $19): https://www.certifyforce.com/practice-exams