Salesforce Migration Deep Dive
Overview
Comprehensive guide for migrating data to/from Salesforce: ETL patterns using Bulk API 2.0, data mapping between CRM schemas, record relationship preservation, and validation.
Prerequisites
- Source and target Salesforce orgs (or external CRM)
- jsforce with Bulk API 2.0 access
- Understanding of sObject relationships and External IDs
- Staging sandbox for dry runs
Migration Types
| Type | Complexity | Duration | Tool |
|---|
| CSV import (< 50K records) | Low | Hours | Data Import Wizard / Bulk API |
| CRM-to-Salesforce | Medium | Weeks | Custom ETL with jsforce |
| Org-to-org migration | Medium | Weeks | SFDX + Bulk API |
| Full re-platform | High | Months | Custom ETL + change management |
Instructions
Step 1: Data Assessment
const conn = await getConnection();
const objectCounts = await Promise.all(
['Account', 'Contact', 'Lead', 'Opportunity', 'Case'].map(async (obj) => {
const result = await conn.query(`SELECT COUNT(Id) total FROM ${obj}`);
return { object: obj, count: result.records[0].total };
})
);
console.table(objectCounts);
const limits = await conn.request('/services/data/v59.0/limits/');
console.log(`Data storage: ${limits.DataStorageMB.Max - limits.DataStorageMB.Remaining}/${limits.DataStorageMB.Max} MB`);
Step 2: Schema Mapping
interface FieldMapping {
source: string;
target: string;
transform?: (value: any) => any;
required: boolean;
}
const accountMappings: FieldMapping[] = [
{ source: 'company_name', target: 'Name', required: true },
{ source: 'industry_code', target: 'Industry', required: false,
transform: (code) => INDUSTRY_MAP[code] || 'Other' },
{ source: 'annual_rev', target: 'AnnualRevenue', required: false,
transform: (v) => typeof v === 'string' ? parseFloat(v.replace(/[$,]/g, '')) : v },
{ source: 'website_url', target: 'Website', : },
{ : , : , : },
{ : , : , : },
];
(): <, > {
: <, > = {};
( mapping mappings) {
value = source[mapping.];
(value === || value === ) {
(mapping.) ();
;
}
(mapping.) value = mapping.(value);
target[mapping.] = value;
}
target;
}
Step 3: Migration Order (Respecting Relationships)
Migration order matters! Parent objects must be loaded before children.
1. Account (no dependencies)
2. Contact (depends on Account via AccountId)
3. Opportunity (depends on Account via AccountId)
4. OpportunityContactRole (depends on Opportunity + Contact)
5. Case (depends on Account + Contact)
6. Task / Event (depends on Contact via WhoId, Account via WhatId)
Use External IDs to resolve relationships without knowing Salesforce IDs:
- Create External_ID__c on Account, Contact, Opportunity
- Use external ID references in child records
Step 4: Bulk Migration with External ID Relationships
import { getConnection } from './salesforce/connection';
import fs from 'fs';
const conn = await getConnection();
const accountCsv = `Name,Industry,External_ID__c
Acme Corp,Technology,EXT-ACME-001
Globex Inc,Manufacturing,EXT-GLOBEX-002
Initech LLC,Consulting,EXT-INITECH-003`;
const accountResults = await conn.bulk2.loadAndWaitForResults({
object: 'Account',
operation: 'upsert',
externalIdFieldName: 'External_ID__c',
input: accountCsv,
});
console.log(`Accounts: ${accountResults.successfulResults.length} success, ${accountResults.failedResults.length} failed`);
const contactCsv = `FirstName,LastName,Email,Account.External_ID__c,External_ID__c
Jane,Smith,jane@acme.com,EXT-ACME-001,EXT-CONTACT-001
John,Doe,john@globex.com,EXT-GLOBEX-002,EXT-CONTACT-002`;
const contactResults = await conn.bulk2.loadAndWaitForResults({
object: 'Contact',
operation: 'upsert',
externalIdFieldName: 'External_ID__c',
input: contactCsv,
});
Step 5: Validation
async function validateMigration(
sourceCount: number,
objectType: string
): Promise<{ passed: boolean; details: string }> {
const conn = await getConnection();
const result = await conn.query(
`SELECT COUNT(Id) total FROM ${objectType} WHERE External_ID__c != null`
);
const targetCount = result.records[0].total;
let orphans = 0;
if (objectType === 'Contact') {
const orphanResult = await conn.query(
`SELECT COUNT(Id) total FROM Contact WHERE AccountId = null AND External_ID__c != null`
);
orphans = orphanResult.records[0].total;
}
const passed = targetCount === sourceCount && orphans === 0;
return {
passed,
details: `Source: ${sourceCount}, Target: ${targetCount}, Orphans: ${orphans}`,
};
}
Step 6: Rollback Plan
async function rollbackMigration(objectType: string): Promise<void> {
const conn = await getConnection();
const records = await conn.query(
`SELECT Id FROM ${objectType} WHERE External_ID__c != null`
);
const ids = records.records.map((r: any) => r.Id);
for (let i = 0; i < ids.length; i += 200) {
const batch = ids.slice(i, i + 200);
await conn.sobject(objectType).destroy(batch);
}
console.log(`Rolled back ${ids.length} ${objectType} records`);
}
Output
- Data assessment with record counts and storage usage
- Field mapping layer transforming source to Salesforce schema
- Bulk API migration respecting parent-child relationships
- External ID-based relationship resolution (no hardcoded IDs)
- Validation and rollback procedures
Error Handling
| Error | Cause | Solution |
|---|
DUPLICATE_VALUE on External_ID__c | Re-running migration | Use upsert instead of insert |
INVALID_CROSS_REFERENCE_KEY | Parent record not found | Verify parent loaded first, check External ID values |
STORAGE_LIMIT_EXCEEDED | Org storage full | Delete test data or upgrade storage |
| Bulk job timeout | Very large dataset | Split into smaller jobs (< 100M records) |
| Field mapping errors | Source schema mismatch | Validate transform functions with sample data first |
Resources
Next Steps
For advanced troubleshooting, see salesforce-advanced-troubleshooting.
