Bulk Data Migration

CA5
Tera Contributor

4 hours ago

How can we migrate 876K records/data which comes from many tables including attachments (if needed) from one Instance to another Instance at one time? Can this be achieved using Scheduled jobs, REST API?

0 Helpfuls
  • 147 Views
1 REPLY 1

KrishnaMohan
Giga Sage

3 hours ago - last edited 3 hours ago

Hi @CA5 

Depends on whether this is a one-time migration (e.g., a "lift and shift" to a new instance) or a continuous sync.

 

Option 1 - One-Time Migration: XML Export/Import (Best for Integrity)

For a one-time move of nearly 1 million records, exporting to XML is often the cleanest method. XML preserves sys_id values, which is critical for maintaining references between tables (e.g., ensuring an Incident still points to the correct User).

  • Process: Export records from the source instance in chunks (to avoid timeouts) and import them into the target instance.

  • Attachments: You must specifically export/import the sys_attachment and sys_attachment_doc tables.

  • Caveat: You cannot do 876K in a single export. You should batch them (e.g., 50K–100K at a time) using encoded queries.

Option -2 Instance Data Replication (IDR)

If you have the licensing, IDR is the modern, ServiceNow-native way to sync data between instances.

  • Pros: It handles bulk data efficiently and manages the transformation of data.

  • Cons: Requires a specific subscription and might be "overkill" if you never intend to sync these instances again

Option -3 Import Sets & Transform Maps 

This involves pulling data from the source using a Data Source (like a JDBC connection or a REST call) into a Staging Table.

  • Pros: Allows you to clean and map data during the migration.

  • Cons: More configuration effort; requires careful handling of attachments via a separate script.

Yes we can use Scheduled Jobs and REST APIs
These are perfect for orchestrating the migration in the background. A scheduled job can trigger a script that fetches data in batches (using sysparm_offset and sysparm_limit) to prevent the instance from "hanging.

 

https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB0727636

If this helped to answer your query, please mark it helpful & accept the solution.
Thanks!
Krishnamohan

0 Helpfuls