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我有一个(全新的)Rails 5 项目,当我尝试运行迁移时它抛出错误。
(我在使用 PostgreSQL 9.4 的 Raspberry Pi 上运行 Ruby 2.2.4,但是当我第一次尝试使用 SQLite 运行迁移时弹出相同的错误消息。)
到目前为止,我唯一的迁移是非常基础的:
class CreateAuthors < ActiveRecord::Migration[5.0]
def change
create_table :authors do |t|
t.string :username
t.timestamps
end
end
end
当我运行 rake db:migrate
时,这会产生以下输出。
pi@raspberrypi:~/projects/gnn $ rake db:migrate
== 20160915091621 CreateAuthors: migrating ====================================
-- create_table(:authors, {})
-> 0.0283s
== 20160915091621 CreateAuthors: migrated (0.0287s) ===========================
rake aborted!
StandardError: An error has occurred, this and all later migrations canceled:
undefined method `value_for_database' for #<Array:0x2a10470>
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `block in exec_no_cache'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `each'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `map'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `exec_no_cache'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:587:in `execute_and_clear'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql/database_statements.rb:103:in `exec_query'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql/database_statements.rb:135:in `exec_insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:124:in `insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/query_cache.rb:14:in `insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/relation.rb:65:in `insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:554:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/counter_cache.rb:128:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/locking/optimistic.rb:75:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/attribute_methods/dirty.rb:123:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:302:in `block in _create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:97:in `__run_callbacks__'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:750:in `_run_create_callbacks'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:302:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/timestamp.rb:68:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:534:in `create_or_update'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:298:in `block in create_or_update'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:97:in `__run_callbacks__'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:750:in `_run_save_callbacks'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:298:in `create_or_update'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:152:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/validations.rb:50:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/attribute_methods/dirty.rb:30:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:324:in `block in save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:395:in `block in with_transaction_returning_status'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:230:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:211:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:392:in `with_transaction_returning_status'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:324:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/suppressor.rb:45:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:51:in `create!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1247:in `record_version_state_after_migrating'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1212:in `block in execute_migration_in_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1279:in `block in ddl_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:232:in `block in transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/transaction.rb:189:in `within_new_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:232:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:211:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1279:in `ddl_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1210:in `execute_migration_in_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1183:in `block in migrate_without_lock'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1182:in `each'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1182:in `migrate_without_lock'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1131:in `block in migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1298:in `with_advisory_lock'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1131:in `migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1005:in `up'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:983:in `migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/tasks/database_tasks.rb:161:in `migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/railties/databases.rake:58:in `block (2 levels) in <top (required)>'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/rake-11.2.2/exe/rake:27:in `<top (required)>'
NoMethodError: undefined method `value_for_database' for #<Array:0x2a10470>
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `block in exec_no_cache'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `each'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `map'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:597:in `exec_no_cache'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql_adapter.rb:587:in `execute_and_clear'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql/database_statements.rb:103:in `exec_query'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql/database_statements.rb:135:in `exec_insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:124:in `insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/query_cache.rb:14:in `insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/relation.rb:65:in `insert'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:554:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/counter_cache.rb:128:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/locking/optimistic.rb:75:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/attribute_methods/dirty.rb:123:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:302:in `block in _create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:97:in `__run_callbacks__'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:750:in `_run_create_callbacks'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:302:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/timestamp.rb:68:in `_create_record'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:534:in `create_or_update'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:298:in `block in create_or_update'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:97:in `__run_callbacks__'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:750:in `_run_save_callbacks'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/callbacks.rb:298:in `create_or_update'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:152:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/validations.rb:50:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/attribute_methods/dirty.rb:30:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:324:in `block in save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:395:in `block in with_transaction_returning_status'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:230:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:211:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:392:in `with_transaction_returning_status'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:324:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/suppressor.rb:45:in `save!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:51:in `create!'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1247:in `record_version_state_after_migrating'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1212:in `block in execute_migration_in_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1279:in `block in ddl_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:232:in `block in transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/transaction.rb:189:in `within_new_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:232:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:211:in `transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1279:in `ddl_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1210:in `execute_migration_in_transaction'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1183:in `block in migrate_without_lock'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1182:in `each'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1182:in `migrate_without_lock'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1131:in `block in migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1298:in `with_advisory_lock'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1131:in `migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:1005:in `up'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/migration.rb:983:in `migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/tasks/database_tasks.rb:161:in `migrate'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/activerecord-5.0.0.1/lib/active_record/railties/databases.rake:58:in `block (2 levels) in <top (required)>'
/home/pi/.rvm/gems/ruby-2.2.4@gnn/gems/rake-11.2.2/exe/rake:27:in `<top (required)>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)
编辑也许值得一提的是 rake db:create
运行良好。
这也是我的 database.yml
文件,以防我在那里遗漏了一些东西(我对 PostgreSQL 很陌生)
default: &default
adapter: postgresql
encoding: unicode
pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
development:
<<: *default
database: gnn_dev
username: gnn
password: Lorem123
host: localhost
port: 5432
最佳答案
我在开发过程中遇到了同样的问题。找到原因了。
在我的例子中,我添加了一个新的 gem“imgurapi”,它将“to_hash”添加到 Array 对象
class Array # :nodoc:
# Skipped code
def to_hash # :nodoc:
inject({}) { |hsh, (k,v)| hsh[k] = v ; hsh }
end unless method_defined?(:to_hash)
end
结果是在 gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql/database_statements.rb:135 中调用代码
将 exec_query(sql, name, binds)
: in 'exec_insert'binds
变量从 Array 转换为 Hash 类型的原因,这里描述得很好 https://makandracards.com/makandra/36013-heads-up-ruby-implicitly-converts-a-hash-to-keyword-arguments .结果我们遇到了错误,因为这种转换是意外的。
解决方案
找到为 Array 定义“to_hash”方法的 gem 并删除该定义。祝你好运!
关于ruby-on-rails - 无方法错误 : undefined method `value_for_database' for #<Array> (Rails 5),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/39507696/
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下面的函数一直返回这个错误信息。我认为可能是 double_precision 字段类型导致了这种情况,我尝试使用 CAST,但要么不是这样,要么我没有做对...帮助? 这是错误: ERROR: i
这个问题已经有答案了: Syntax error due to using a reserved word as a table or column name in MySQL (1 个回答) 已关闭
我的数据库有这个小问题。 我创建了一个表“articoli”,其中包含商品的品牌、型号和价格。 每篇文章都由一个 id (ID_ARTICOLO)` 定义,它是一个自动递增字段。 好吧,现在当我尝试插
我是新来的。我目前正在 DeVry 在线学习中级 C++ 编程。我们正在使用 C++ Primer Plus 这本书,到目前为止我一直做得很好。我的老师最近向我们扔了一个曲线球。我目前的任务是这样的:
这个问题在这里已经有了答案: What is an undefined reference/unresolved external symbol error and how do I fix it?
我的网站中有一段代码有问题;此错误仅发生在 Internet Explorer 7 中。 我没有在这里发布我所有的 HTML/CSS 标记,而是发布了网站的一个版本 here . 如您所见,我在列中有
如果尝试在 USB 设备上构建 node.js 应用程序时在我的树莓派上使用 npm 时遇到一些问题。 package.json 看起来像这样: { "name" : "node-todo",
在 Python 中,您有 None单例,在某些情况下表现得很奇怪: >>> a = None >>> type(a) >>> isinstance(a,None) Traceback (most
这是我的 build.gradle (Module:app) 文件: apply plugin: 'com.android.application' android { compileSdkV
我是 android 的新手,我的项目刚才编译和运行正常,但在我尝试实现抽屉导航后,它给了我这个错误 FAILURE: Build failed with an exception. What wen
谁能解释一下?我想我正在做一些非常愚蠢的事情,并且急切地等待着启蒙。 我得到这个输出: phpversion() == 7.2.25-1+0~20191128.32+debian8~1.gbp108
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