Backend · Mid-level · Theory

You need to rename a column in a large table, and the service deploys without downtime via rolling updates. How would you carry out this change?

~4 min by voice

How to approach it

This checks whether the candidate understands that during a rolling deploy the old and new code work against the same DB schema at the same time, and whether they can carry out an incompatible schema change via expand/contract without downtime or locking, and with the ability to roll back.

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Topics

ci cd database migrations deployment

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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 · ~4 min