Organizations often rely on multiple systems to manage their data. When this information needs to be available in ServiceNow, manually importing files isn't always practical. APIs provide a more efficient way to move data between external applications and ServiceNow.
In this blog, we'll look at how API-based data imports work in ServiceNow and the two commonly used approaches: the Table API and the Import Set API.
What Is an API-Based Data Import?
API-based data import allows an external application to send data to ServiceNow programmatically.
For example, an HR system may contain employee information that needs to be available in ServiceNow. Instead of manually uploading employee records, the external system can send the data through an API.
A typical flow looks like:
External System → API → ServiceNow → Data Processing → ServiceNow Table
The approach you use depends on how the incoming data needs to be handled.
Table API vs. Import Set API
ServiceNow provides several APIs, but the Table API and Import Set API are commonly used for bringing external data into the platform.
1. Table API
The Table API allows applications to create, read, update, and delete records directly in ServiceNow tables.
For example, an external monitoring application can create an incident in ServiceNow using a REST request:
POST /api/now/table/incidentA request might contain:
{
"short_description": "Email service is unavailable",
"urgency": "2"
}
The Table API is a good choice when the incoming data already matches the structure of the target ServiceNow table, and you need direct record operations.
2. Import Set API
The Import Set API is useful when incoming data needs to be staged, mapped, or transformed before being added to the target table. It’s normally used when we need to upload data in bulk.
The basic flow is:
External System → Import Set Table → Transform Map → Target Table
For example, an external HR system might send:
{
"employee_id": "EMP1025",
"employee_name": "John Smith",
"department": "IT"
}
The Import Set API can receive this data in a staging table, while a Transform Map determines how those fields are mapped and transformed before reaching the target table.
Which Approach Should You Use?
The choice largely depends on the complexity of the data and the type of integration.
| Requirement | Recommended API |
| Create or update records directly | Table API |
| Read ServiceNow records | Table API |
| Data required transformation | Import Set API |
| External and ServiceNow fields differ | Import Set API |
| Data needs to pass through a staging table | Import Set API |
For simple, direct record operations, the Table API is usually sufficient. When data requires additional processing or transformation, the Import Set API provides more flexibility.
Key Considerations
Before implementing an API-based import, consider:
- Authentication and permissions: Make sure the integration user has only the access required for the relevant tables and operations.
- Data mapping: Confirm that external fields and ServiceNow fields are mapped correctly.
- Duplicate handling: Define how existing records will be identified and whether they should be updated or new records created.
- Error handling: Account for invalid data, missing fields, failed requests, and transformation errors.
- Testing: Test the integration with a small data set before processing larger volumes.
Conclusion
API-based imports provide a reliable way to connect ServiceNow with external applications and keep data synchronized.
The Table API is well suited for direct CRUD operations, while the Import Set API is a better fit when data needs staging, mapping, or transformation.
Choosing the right approach—and planning for authentication, data quality, mapping, and error handling—can make ServiceNow integrations more reliable and easier to maintain.