Scenarios & trade-offsMediumSDE-3

You need to change how a 500-million-row Postgres table stores amounts, from a float column to an integer column in paise, while the system serves live traffic. How do you do it without downtime?

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FlipkartRazorpayZerodha

Think first

Answer out loud as you would in the room — clarify, give numbers, name the trade-off — then compare with the model answer.

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