Data migration: moving verified, cleansed data into the new system

A data migration usually follows five steps: analysis of the source and target systems, field mapping with cleansing rules, development of the migration scripts, trial runs with reconciliation, and finally the switchover on the cutover date. What matters is that the migration is repeatable and every run is verified. That way, errors show up in testing, not in live operation.

The effort depends on data volumes, the number of sources and, above all, data quality. A manageable migration, for example from Excel or a single database, is possible in the Starter package from €2,500, while migrations from several legacy systems with extensive cleansing usually fall under the Professional package from €8,000. You will receive the exact quote after the free initial consultation and a first look at your data.

A good plan describes scope and sources, field mapping, cleansing rules, responsibilities, test runs with acceptance criteria, the cutover date with a time window and a fallback plan. It also includes the decision on which legacy data is deliberately not carried over. We create this plan together with your business department.

First the schema is transferred and adapted to the quirks of the target database, for example with data types, character sets and auto-incrementing IDs. Then the data is transferred with tools such as pgloader or custom scripts, and the application's queries are adapted. Finally, we compare record counts and the results of important queries between the old and new database.

A simple transfer can be done in a few weeks. Most of the time usually goes into analysis and cleansing, not the actual transfer. We plan the switchover itself so that it happens in a short, agreed time window.

The migration is a good opportunity for a cleanup. Together with you, we decide which data is transferred, archived or deleted, for example based on your deletion policy. Which retention and deletion obligations apply to you should be assessed by your data protection officer or legal advisor. Our information does not replace legal advice.