How can I change the data type on rails?

Question

I want to modify the data type from string to text, and I followed the tutorial from

Changing a column type to longer strings in rails

and run rake db:migrate and rake db:rollback but it gave me an error message

== 20160203133535 ChangeNameToProfessors: migrating =========================== -- change_column(:professors, :name, :text) rake aborted! StandardError: An error has occurred, this and all later migrations canceled:

How can I solve it?

thank for answering!

you can start by sharing the actual error you get :) – sevenseacat Feb 03 '16 at 14:37 — sevenseacat, Feb 03 '16 at 14:37
give some more error message. – Arup Rakshit Feb 03 '16 at 14:42 — Arup Rakshit, Feb 03 '16 at 14:42
Please show us the content of your migration file – Laurens Feb 03 '16 at 14:42 — Laurens, Feb 03 '16 at 14:42

Laurens · Accepted Answer · 2016-02-03T15:56:48.230

0

If you just want to change a single column:

def change
  change_column :table_name, :column_name, :text
end

If you want to perform a rollback, then first perform the rollback before changing your (already existing) migration file. You cannot perform a rollback with a changed migration file, this is what likely happens in your scenario.

After the rollback change the migration file to the correct (new) column, and migrate again.

edited Feb 03 '16 at 15:56

answered Feb 03 '16 at 14:43

Laurens

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OP did, as I see in the error message `change_column(:professors, :name, :text)`. something wrong in other place or I dunno. – Arup Rakshit Feb 03 '16 at 14:49

How can I change the data type on rails?

1 Answers1