Data Modeling and Management · Topic 3 of 3
Data Import, Export and External Data Sources
Salesforce data options: Data Import Wizard vs Data Loader, upsert with External IDs, Data Export Service, and Salesforce Connect external objects.
- 4 min
- Data Import Wizard: browser-based, up to 50,000 records, limited objects, no delete or export.
- Data Loader: any API object, large volumes, upsert, delete, hard delete, export.
- Upsert matches on record ID or External ID.
What it is
Apps need data loaded into them, backed up out of them, and sometimes shown from other systems without copying. Salesforce offers different tools for each job: the Data Import Wizard and Data Loader to load data, the Data Export Service and Data Loader to export it, and Salesforce Connect to view external data in place.
How it works
Data Import Wizard versus Data Loader
| Feature | Data Import Wizard | Data Loader |
|---|---|---|
| Where it runs | In Setup, in the browser | Installed client application |
| Record volume | Up to 50,000 records per import | Large volumes, up to millions of records |
| Objects | Accounts, contacts, leads, solutions, campaign members, person accounts and custom objects | Any object the API supports |
| Operations | Insert, update, insert or update | Insert, update, upsert, delete, hard delete, export |
| Duplicate handling | Built-in matching by name, email or ID | Matching by record ID or External ID |
Choose the wizard for simple loads of supported objects within its limit. Choose Data Loader for large volumes, objects the wizard does not support, deletes, exports or scheduled command-line loads.
Upsert and External IDs
Upsert updates a record if it already exists and inserts it if it does not. Matching uses the Salesforce record ID or an External ID field. External IDs also let you set relationships during a load by referring to the parent's external ID instead of its Salesforce ID.
Before and during a load
- Clean the data and map columns to fields.
- Load parents before children, such as accounts before contacts.
- Validation rules, required fields and duplicate rules apply to imported records, so they can reject rows.
- Automation such as record-triggered flows runs on loaded records; consider its effect on large loads.
Exporting data
| Tool | Use |
|---|---|
| Data Export Service | Weekly or monthly export of the org's data as CSV files, from Setup |
| Data Loader export | Export selected objects and fields, including on a schedule from the command line |
| Reports | Export the results of a report |
External data with Salesforce Connect
Salesforce Connect shows data that lives in another system as external objects, without copying it into Salesforce. Users can see external records on pages, in related lists and in search, and the data stays in its source.
| Adapter | Connects to |
|---|---|
| OData 2.0 / 4.0 | Systems that expose an OData service |
| Cross-org | Another Salesforce org |
| Custom adapter | Other sources, built by a developer with Apex |
Relationships with external objects use external lookup and indirect lookup fields. Use Salesforce Connect when data is large, changes often in the source, and users only need to see it, not copy it.
A worked example: a manufacturer keeps millions of order lines in its ERP, and reps need to see a customer's orders on the account page. Copying them nightly would duplicate data and quickly go out of date. The builder sets up Salesforce Connect with the ERP's OData service, creates an Order Line external object, and relates it to Account through an indirect lookup on the account's ERP number field.
"View external data in real time without storing it in Salesforce" points to Salesforce Connect and external objects.
How the exam asks about this
- "Import 20,000 leads with duplicate checking." Data Import Wizard.
- "Delete 300,000 old records." Data Loader.
- "Show records from an ERP without copying them." Salesforce Connect.
What to remember for the exam
- Data Import Wizard: browser-based, up to 50,000 records, limited objects, no delete or export.
- Data Loader: any API object, large volumes, upsert, delete, hard delete, export.
- Upsert matches on record ID or External ID.
- Load parents before children; validation rules still apply.
- Salesforce Connect shows external data as external objects without copying it.
Hard delete in Data Loader bypasses the Recycle Bin. Deleted records cannot be restored from it.
Common mistakes
Choosing the Data Import Wizard for an object it does not support. Use Data Loader.
Copying large, fast-changing external data into Salesforce. Salesforce Connect shows it in place.
Loading child records before their parents. The relationships cannot be set.
Check yourself
Which tool can delete large numbers of records?
Data Loader, which supports delete and hard delete.
What does upsert do?
It updates records that match on record ID or External ID and inserts records that do not match.
How can users see external system data in Salesforce without importing it?
With Salesforce Connect and external objects.
Topic 3 of 3 in Data Modeling and Management
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