Class | ActiveRecord::ConnectionAdapters::Table
In: | lib/active_record/connection_adapters/abstract/schema_definitions.rb
Parent: | Object

Represents a SQL table in an abstract way for updating a table. Also see TableDefinition and SchemaStatements#create_table

Available transformations are:

      change_table :table do |t|
        t.column
        t.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

### Methods

belongs_to change change_default column index new references remove remove_belongs_to remove_index remove_references remove_timestamps rename timestamps

### Public Class methods

new(table_name, base)

### Public Instance methods

belongs_to(*args)

Alias for references

change(column_name, type, options = {})

Changes the column‘s definition according to the new options. See TableDefinition#column for details of the options you can use.

##### Examples

     t.change(:name, :string, :limit => 80)
     t.change(:description, :text)

change_default(column_name, default)

Sets a new default value for a column. See SchemaStatements#change_column_default

##### Examples

     t.change_default(:qualification, 'new')
     t.change_default(:authorized, 1)

column(column_name, type, options = {})

Adds a new column to the named table. See TableDefinition#column for details of the options you can use.

##### Example

###### Creating a simple column

     t.column(:name, :string)

index(column_name, options = {})

Adds a new index to the table. `column_name` can be a single Symbol, or an Array of Symbols. See SchemaStatements#add_index

##### Examples

###### Creating a simple index

     t.index(:name)

###### Creating a unique index

     t.index([:branch_id, :party_id], :unique => true)

###### Creating a named index

     t.index([:branch_id, :party_id], :unique => true, :name => 'by_branch_party')

references(*args)

Adds a reference. Optionally adds a `type` column. `references` and `belongs_to` are acceptable.

##### Examples

     t.references(:goat)
     t.references(:goat, :polymorphic => true)
     t.belongs_to(:goat)

remove(*column_names)

Removes the column(s) from the table definition.

##### Examples

     t.remove(:qualification)
     t.remove(:qualification, :experience)

remove_belongs_to(*args)

Alias for remove_references

remove_index(options = {})

Removes the given index from the table.

##### Examples

###### Remove the suppliers_name_index in the suppliers table

      t.remove_index :name

###### Remove the index named accounts_branch_id_index in the accounts table

      t.remove_index :column => :branch_id

###### Remove the index named accounts_branch_id_party_id_index in the accounts table

      t.remove_index :column => [:branch_id, :party_id]

###### Remove the index named by_branch_party in the accounts table

      t.remove_index :name => :by_branch_party

remove_references(*args)

Removes a reference. Optionally removes a `type` column. `remove_references` and `remove_belongs_to` are acceptable.

##### Examples

     t.remove_references(:goat)
     t.remove_references(:goat, :polymorphic => true)
     t.remove_belongs_to(:goat)

remove_timestamps()

Removes the timestamp columns (created_at and updated_at) from the table.

##### Example

     t.remove_timestamps

rename(column_name, new_column_name)

Renames a column.

##### Example

     t.rename(:description, :name)

timestamps()

Adds timestamps (created_at and updated_at) columns to the table. See SchemaStatements#add_timestamps

##### Example

     t.timestamps

[Validate]