> For the complete documentation index, see [llms.txt](https://kelby.gitbook.io/rails-beginner-s-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kelby.gitbook.io/rails-beginner-s-guide/activerecord_migration/activerecord_migration_connectionadapters/connection-adapter_table.md).

# Table

**简单划分 change\_table**

使用 create\_table 时，传递给 block 的参数 `t` 就是此类型：

```ruby
change_table :table_name do |t|
  # t.class
  # => ActiveRecord::ConnectionAdapters::Table
end
```

相关模块或方法，可以参考：TableDefinition 和 SchemaStatements#create\_table

支持的数据类型或操作有:

```ruby
change_table :table do |t|
  t.column
  t.index
  t.rename_index
  t.timestamps
  t.change
  t.change_default
  t.rename
  t.references
  t.belongs_to
  t.string
  t.text
  t.integer
  t.float
  t.decimal
  t.datetime
  t.timestamp
  t.time
  t.date
  t.binary
  t.boolean
  t.remove
  t.remove_references
  t.remove_belongs_to
  t.remove_index
  t.remove_timestamps
end
```

除上述外，还有：

```
column_exists?
index_exists?

change, change_default

remove, remove_index, remove_timestamps
remove_belongs_to & remove_references

rename, rename_index

column
index
timestamps
belongs_to & references
```

> Note: 这里有一些方法是通过元编程生成的，查文档找不到它们，可能通过 ActiveRecord::ConnectionAdapters::Table.public\_instance\_methods(false) 查看。

列举如下：

```
:column
:column_exists?
:index
:index_exists?
:rename_index
:timestamps
:change
:change_default
:remove
:remove_index
:remove_timestamps
:rename
:references
:belongs_to
:remove_references
:remove_belongs_to
:string
:text
:integer
:float
:decimal
:datetime
:timestamp
:time
:date
:binary
:boolean
```


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