rake 迁移中止：找不到表“角色”

【问题标题】：rake migration aborted: could not find table 'roles'rake 迁移中止：找不到表“角色”
【发布时间】：2012-10-02 22:05:06
【问题描述】：

我刚刚继承了我试图为其运行迁移的代码，但我不断收到 rake aborted 错误。我遇到过其他似乎有类似问题的人，但大多数涉及 Heroku，我正在尝试在本地运行它（开始）。

我尝试使用 PostgreSQL 和 SQLite 进行故障排除，但都产生了相同的问题。引用的表“角色”是调用的第二个迁移，所以我很难弄清楚是什么导致它无法构建。非常感谢任何和所有的帮助。提前致谢。

以下是角色迁移：

class CreateRoles < ActiveRecord::Migration
  def change
    create_table :roles do |t|
      t.string :name

      t.timestamps
    end
  end
end

这是 SQLite 的跟踪：

** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
rake aborted!
Could not find table 'roles'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/sqlite_adapter.rb:470:in `table_structure'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/sqlite_adapter.rb:351:in `columns'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/schema_cache.rb:12:in `block in initialize'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:228:in `yield'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:228:in `default'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:228:in `columns'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:248:in `column_names'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:261:in `column_methods_hash'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/dynamic_matchers.rb:69:in `all_attributes_exists?'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/dynamic_matchers.rb:27:in `method_missing'
/Users/sa/Documents/AptanaWorkspace/recprototype/config/initializ
ers/constants.rb:1:in `<top (required)>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:245:in `load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:245:in `block in load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:236:in `load_dependency'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:245:in `load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/engi
ne.rb:588:in `block (2 levels) in <class:Engine>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/engi
ne.rb:587:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/engi
ne.rb:587:in `block in <class:Engine>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:30:in `instance_exec'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:30:in `run'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:55:in `block in run_initializers'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:54:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:54:in `run_initializers'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/appl
ication.rb:136:in `initialize!'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/rail
tie/configurable.rb:30:in `method_missing'
/Users/sa/Documents/AptanaWorkspace/recprototype/config/environme
nt.rb:5:in `<top (required)>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:251:in `require'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:251:in `block in require'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:236:in `load_dependency'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:251:in `require'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/appl
ication.rb:103:in `require_environment!'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/appl
ication.rb:292:in `block (2 levels) in initialize_tasks'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:205:in `call'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:205:in `block in execute'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:200:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:200:in `execute'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:158:in `block in invoke_with_call_chain'
/Users/sa/.rvm/rubies/ruby-1.9.2-p318/lib/ruby/1.9.1/monitor.rb:201:in
 `mon_synchronize'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:151:in `invoke_with_call_chain'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:176:in `block in invoke_prerequisites'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:174:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:174:in `invoke_prerequisites'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:157:in `block in invoke_with_call_chain'
/Users/sa/.rvm/rubies/ruby-1.9.2-p318/lib/ruby/1.9.1/monitor.rb:201:in
 `mon_synchronize'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:151:in `invoke_with_call_chain'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:144:in `invoke'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:116:in `invoke_task'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:94:in `block (2 levels) in top_level'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:94:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:94:in `block in top_level'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:133:in `standard_exception_handling'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:88:in `top_level'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:66:in `block in run'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:133:in `standard_exception_handling'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:63:in `run'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/bin/rake:33:in `
<top (required)>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/bin/rake:19:in `load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/bin/rake:19:in `<main>'
Tasks: TOP => db:migrate => environment

这是 PostgreSQL 的跟踪：

** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
rake aborted!
PG::Error: ERROR:  relation "roles" does not exist
LINE 4:              WHERE a.attrelid = '"roles"'::regclass
                                        ^
:             SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a
.attnotnull
              FROM pg_attribute a LEFT JOIN pg_attrdef d
                ON a.attrelid = d.adrelid AND a.attnum = d.adnum
             WHERE a.attrelid = '"roles"'::regclass
               AND a.attnum > 0 AND NOT a.attisdropped
             ORDER BY a.attnum
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/postgresql_adapter.rb:1106:in `async_exec'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/postgresql_adapter.rb:1106:in `exec_no_cache'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/postgresql_adapter.rb:650:in `block in exec_query'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/abstract_adapter.rb:280:in `block in log'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/notifications/instrumenter.rb:20:in `instrument'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/abstract_adapter.rb:275:in `log'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/postgresql_adapter.rb:649:in `exec_query'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/postgresql_adapter.rb:1231:in `column_definitions'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/postgresql_adapter.rb:845:in `columns'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/connection_adapters/schema_cache.rb:12:in `block in initialize'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:228:in `yield'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:228:in `default'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:228:in `columns'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:248:in `column_names'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/model_schema.rb:261:in `column_methods_hash'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/dynamic_matchers.rb:69:in `all_attributes_exists?'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activerecord-3.2.1/lib/active
_record/dynamic_matchers.rb:27:in `method_missing'
/Users/sa/Documents/AptanaWorkspace/recprototype/config/initializ
ers/constants.rb:1:in `<top (required)>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:245:in `load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:245:in `block in load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:236:in `load_dependency'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:245:in `load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/engi
ne.rb:588:in `block (2 levels) in <class:Engine>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/engi
ne.rb:587:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/engi
ne.rb:587:in `block in <class:Engine>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:30:in `instance_exec'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:30:in `run'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:55:in `block in run_initializers'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:54:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/init
ializable.rb:54:in `run_initializers'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/appl
ication.rb:136:in `initialize!'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/rail
tie/configurable.rb:30:in `method_missing'
/Users/sa/Documents/AptanaWorkspace/recprototype/config/environme
nt.rb:5:in `<top (required)>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:251:in `require'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:251:in `block in require'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:236:in `load_dependency'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/activesupport-3.2.1/lib/activ
e_support/dependencies.rb:251:in `require'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/appl
ication.rb:103:in `require_environment!'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/railties-3.2.1/lib/rails/appl
ication.rb:292:in `block (2 levels) in initialize_tasks'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:205:in `call'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:205:in `block in execute'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:200:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:200:in `execute'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:158:in `block in invoke_with_call_chain'
/Users/sa/.rvm/rubies/ruby-1.9.2-p318/lib/ruby/1.9.1/monitor.rb:201:in
 `mon_synchronize'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:151:in `invoke_with_call_chain'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:176:in `block in invoke_prerequisites'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:174:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:174:in `invoke_prerequisites'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:157:in `block in invoke_with_call_chain'
/Users/sa/.rvm/rubies/ruby-1.9.2-p318/lib/ruby/1.9.1/monitor.rb:201:in
 `mon_synchronize'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:151:in `invoke_with_call_chain'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/task.rb
:144:in `invoke'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:116:in `invoke_task'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:94:in `block (2 levels) in top_level'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:94:in `each'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:94:in `block in top_level'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:133:in `standard_exception_handling'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:88:in `top_level'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:66:in `block in run'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:133:in `standard_exception_handling'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/lib/rake/applica
tion.rb:63:in `run'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/gems/rake-0.9.2.2/bin/rake:33:in `
<top (required)>'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/bin/rake:19:in `load'
/Users/sa/.rvm/gems/ruby-1.9.2-p318/bin/rake:19:in `<main>'
Tasks: TOP => db:migrate => environment

【问题讨论】：

  • 第一次迁移做什么（在这次迁移之前）？
  • 您的迁移是否以正确的顺序运行？尝试使用 rake db:migrate VERSION=20098252345 手动执行它们

标签： ruby-on-rails migration rake abort


【解决方案1】：

似乎config/initializers/constants.rb 正在对需要存在角色表的Role 类执行某些操作。当您运行迁移时，初始化程序会正常加载，因此您的应用会因为该表尚不存在而崩溃。

在角色表上添加此依赖项的开发人员可能是在他们的机器上创建角色表之后才这样做的。

你可以

  • 尝试加载架构而不是运行迁移 rake db:schema:load 假设 schema.rb 已签入。如果加载架构加载初始化程序，这将不起作用 - 我不记得是否是这种情况
  • 从 SQL 转储中恢复数据库
  • 注释掉有问题的代码（或用测试表是否存在将其括起来），然后运行迁移/加载模式 - 所做的任何事情都不太可能对运行迁移至关重要。如果注释掉该代码会导致更多故障，请使用源代码管理将应用程序恢复到最初签入迁移后的状态，希望任何此类问题都更容易解决

【讨论】：

  • 谢谢。我最终注释掉了 constants.rb 代码，然后能够运行迁移。
【解决方案2】：

这不是对您问题的直接答案，但无论如何我都会将其作为答案发布，因为我认为它会对您有所帮助。

您应该使用应用程序的schema.rb 文件，而不是从一开始就运行所有代码的迁移。请注意，这仅在您首次设置已开始工作的现有应用程序时有效（因为它强制创建所有表，因此删除任何内容），但这是在此加载数据库的正确方法案子。迁移意味着增量更改。

要将架构加载到您的数据库中：

rake db:schema:load

然后您的数据库将根据schema.rb 文件进行设置（为此，Rails 会自动更新该文件）。

编辑 问题的原因可能是应用程序中的某些代码在迁移之前加载了引用 roles 表（或更可能是 Role 模型）的代码。当routes.rb 文件中有数据库查询时，这种情况经常发生，但它可能来自调用environment rake 任务时加载的任意数量的文件（:migrate 任务就是这种情况）。

编辑 2 查看您的堆栈跟踪：

/Users/sa/Documents/AptanaWorkspace/recprototype/config/initializ ers/constants.rb:1:in `'

我猜config/initializers/constants.rb 文件有类似Role.all 的内容。每当加载 Rails 环境时都会加载初始化程序（Rails 提供的大多数 rake 任务都是这种情况）。

您仍应使用rake db:schema:load 任务，但您需要在运行前注释掉该行（当然，如果我的理论是正确的）。

【讨论】：

    猜你喜欢
    • 1970-01-01
    • 2013-06-28
    • 1970-01-01
    • 2011-04-21
    • 2012-09-08
    • 2016-05-14
    • 2012-05-25
    • 1970-01-01
    • 2023-03-04
    相关资源
    最近更新 更多
    热门标签
    Java Python linux javascript Mysql C# Docker 算法 前端 SpringBoot Redis Vue spring 设计模式 .net core .net kubernetes c++ 数据库 数据结构 大数据 js 机器学习 微服务 Android Go 程序员 面试 JVM ASP.net core 云原生 人工智能 后端 PHP git CSS golang k8s Nginx Django mybatis 深度学习 多线程 React 架构 devops 爬虫 云计算 Spring Boot LeetCode