In Ruby on Rails, when creating a new record in a table, the id column is not created automatically (there is no auto and primary key), what migration should I create?

Question

Ruby on Rails

How to fix the current table (which migration to create or something) if when creating a new record id creates nothing (nil)???

Answer 1

rails generate migration AddIndexToYourField your_index_field:string:index

or in migration
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