Rake db：migrate error-SQLite3

Question

在執行rake db時，我總是收到以下錯誤：migrate命令：

rake中止！ 發生錯誤，這和所有後來遷移取消： 的SQLite3 ::的SQLException：重複列名：電子郵件：ALTER TABLE 「用戶」 ADD 「電子郵件」 爲varchar（255）DEFAULT '' NOT NULL

我已經還嘗試了命令 - bundle exec rake db：migrate。我跑了 - 追蹤並得到了信息。下面。

**調用分貝：遷移（FIRST_TIME） **調用環境（FIRST_TIME） **執行環境 **調用分貝：load_config（FIRST_TIME） **執行分貝：load_config **執行分貝：遷移 == AddDeviseToUsers：migrating ============================================ === - change_table（：users） rake中止！ 發生錯誤，這和所有後來遷移取消：

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Answer 1

First of all, if you're using devise for authentication,email field is provided by default. The source for the error is: "The email field is also present in users table. That's why whenever you're run db:migrate it shows duplicate column error. 

So drop the users table by giving command ActiveRecord::Migration.drop_table(:users)" in rails console. 

Then, give rails g model user user_name:string mobile_number:integer 

Hope it will helps.