Make a new column (migration) between two other columns?

Question

Is there a quick/easy way to make a migration that adds a new column between two existing columns?

Note: I googled and couldn't find an obvious answer. But I also am curious if it's even good practice (since if for some reason other column/s were removed, then the migration may fail?)

Answer 1

If you haven't commited your changes to production you can reorder migrations by rolling them back and then changing the timestamps in the file name.

If thats not an alternative you can actually re-order the columns on some databases directly with SQL even if its not part of the migrations DSL. Migrations are after all really just a DSL to create SQL strings and run them in a repeatable way across environments.

If you can't generate the SQL you want with the DSL you can always use execute to execute a raw DSL string.

# MySQL example
class ReorderYourTableName  < ActiveRecord::Migration[5.2]
  def change
    execute "alter table yourTableName change column yourColumnName yourColumnName dataType after yourSpecificColumnName;"
  end
end

However on some DBs you can't actually reorder the columns without extensive steps of creating new columns and shuffling the data around.