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You probably could, but you really want your database migrations to clear, repeatable, and dead simple.

I can also imagine edge cases like a migration dropping a column and another recreating it where it may be unclear what the state is, and honestly you don't want to be surprised when you migrate thousands of paying customers' data.

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Another reasonable example is a migration which adds a column ultimately intended to be "not null". The first migration might add the column as nullable, then subsequent migrations and/or server logic populate the column, culminating with a future migration which alters the constraint to be "not null".

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