Data migration
Data migration is the one-time move of records from a source system to a target system, including selecting what moves, transforming it to fit the new model, and proving on evidence that the move was accurate and complete, so the source can finally be retired.
Submit a project Plan a legacy data migrationReviewed by Huy Nguyen (David), CEO · Updated 3 Nov 2026 · 4 min read
This term is one of the entries in the OutsourcingVN glossary of words buyers meet while planning a system change.
Why does data migration matter?
A migration is a project with a defined end, not an ongoing process: the data leaves the old system, lands correctly in the new one, and the move is verified before anyone stops relying on the source. OutsourcingVN is operated by Netbase JSC, and data migration projects that run over time or over budget often do so because the move was treated as a load script rather than something that needs profiling the source and proving the result first.
What is an example of data migration in practice?
A company replacing an old order-management system needs every customer, order and invoice record moved into the new one. The team profiles the old data, finds duplicate customer records and a currency field that was left blank for years of orders in one region, writes a mapping that resolves both issues, and runs the move as a repeatable job rehearsed more than once. Before the old system is switched off, row counts and control totals on both sides are compared and the differences are explained, not just logged as zero errors.
What are the common misreadings of data migration?
Data migration is not only a database engine change: moving the same application's data from one database vendor to another is one kind of data migration, but a move between two different systems also changes the data model and the system of record, which is where most of the mapping and reconciliation work sits. It is also not the same as an application re-platforming, where the software itself is rebuilt or moved onto a new technology stack; a legacy PHP to Laravel migration and a Shopify to WooCommerce migration are examples of that second, broader kind of project, which usually carries a data migration inside it rather than being one. And a migration is not "done" when the load script exits without an error: a green log proves rows were written, not that the right rows, with the right values, reached the target.
What is data migration most often confused with?
| Commonly confused with | What's actually true | Watch out for |
|---|---|---|
| Database engine change | A vendor swap is one kind; moving between different systems also changes the data model | Scoping a cross-system move like a simple engine swap |
| Application re-platforming | Rebuilding the software itself is a broader project that usually contains a data migration | Confusing a re-platform's scope with a migration's |
| "Done" at zero load-script errors | A clean log proves rows were written, not that the right values landed | Skipping row-count and control-total verification |
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Common questions
No. Only the part that moves records from one system of record to another counts; a visual redesign or a hosting change with no change of system does not.
Yes. Some migrations move data in stages or keep both systems live in parallel for a period, but each entity still needs its own one-time point where it is declared moved and reconciled. The cutover entry defines the switch itself.
Which decisions does data migration affect?
Planning the data chapter of a modernization project — profiling what the old system holds, agreeing what moves, writing the mapping with the business and accepting the result on reconciliation evidence — is the subject of the legacy data migration planning guide; moving a CRM's accounts and orders into an ERP follows the same discipline, as the Vtiger CRM to ERP migration guide sets out, and reconciling a ledger's chart of accounts, open items and balances is the same discipline the QuickBooks to Odoo migration guide applies to accounting data. A data migration is usually one chapter of a wider legacy system modernization programme, scoped as legacy application modernization. When you know which systems and records are involved, describe them and Netbase will respond through Netbase's own outsourcing-services platform; submit a project when you are ready.