When I am working on a data import of some kind, I sometimes need to reset the AUTO_INCREMENT value for the id column.
The SQL for this is ALTER TABLE table_name AUTO_INCREMENT = 1;
Just run this in your rails console
replacing 'posts' with your table name.
ActiveRecord::Base.connection.execute("ALTER TABLE posts AUTO_INCREMENT = 1;")
You can change the value of 1 to something higher if you need it to start at maybe 100 for example.
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