QA · Senior · System design

How would you set up testing for a data migration from an old billing system to a new one?

~10 min by voice

How to approach it

The interviewer checks whether the candidate can build a systematic strategy for verifying a risky migration involving money: from mapping and automated reconciliations to parallel calculation, handling dirty legacy data and a ready rollback. They watch whether the candidate understands that matching data doesn't yet guarantee the new system calculates the same way.

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Topics

data migration sql

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~10 min