在Rails 4.0.0,ruby 1.9.3p392(2013-02-22修订版39386)[x86_64-darwin10.8.0]中使用Rake 10.1.1db:在Rails 4.0.0耙过程中迁移错误
我正在研究Rails中的类的应用程序,我犯了一个错误,并删除了在Git中所做的更改。当我去重做项目,跑耙DB迁移,我得到了以下错误消息:
Joses-MacBook-Air:crumblr JRV$ rails generate migration CreateHearts Post_id:integer
invoke active_record
create db/migrate/20140120235500_create_hearts.rb
Joses-MacBook-Air:crumblr JRV$ bundle exec rake db:migrate
== CreateHearts: migrating ===================================================
-- create_table(:hearts)
rake aborted!
An error has occurred, this and all later migrations canceled:
SQLite3::SQLException: table "hearts" already exists: CREATE TABLE "hearts" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "Post_id" integer) /usr/local/rvm/gems/ruby-1.9.3- p392/gems/sqlite3-1.3.8/lib/sqlite3/database.rb:91:in `initialize'
4.0.0/lib/active_record/railties/databases.rake:42:in `block (2 levels) in <top (required)>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)
如何摆脱旧表引用的?
你没有说清楚。通过“旧表引用”,你的意思是你想更新你的schema.rb以匹配现有数据库中的内容,或者你想让数据库进入你的代码库期望的状态?您是否更改了迁移的标识符(时间戳)?数据库应该跟踪上次运行的迁移。 – coreyward