Module: Foreigner::ConnectionAdapters::TableDefinition::InstanceMethods

Defined in:
lib/foreigner/connection_adapters/abstract/schema_definitions.rb

Instance Method Summary collapse

Instance Method Details

#foreign_key(to_table, options = {}) ⇒ Object

Defines a foreign key for the table. to_table can be a single Symbol, or an Array of Symbols.

Examples
Creating a simple foreign key
t.foreign_key(:person)
Defining the column
t.foreign_key(:person, :column => :sender_id)
Specify cascading foreign key
t.foreign_key(:person, :dependent => :delete)



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# File 'lib/foreigner/connection_adapters/abstract/schema_definitions.rb', line 69

def foreign_key(to_table, options = {})
  if @base.supports_foreign_keys?
    to_table = to_table.to_s.pluralize if ActiveRecord::Base.pluralize_table_names
    foreign_keys << ForeignKey.new(@base, to_table, options)
  end
end

#references_with_foreign_keys(*args) ⇒ Object

Adds a :foreign_key option to TableDefinition.references. If :foreign_key is true, a foreign key constraint is added to the table. You can also specify a hash, which is passed as foreign key options.

Examples
Add goat_id column and a foreign key to the goats table.
t.references(:goat, :foreign_key => true)
Add goat_id column and a cascading foreign key to the goats table.
t.references(:goat, :foreign_key => {:dependent => :delete})

Note: No foreign key is created if :polymorphic => true is used.



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# File 'lib/foreigner/connection_adapters/abstract/schema_definitions.rb', line 47

def references_with_foreign_keys(*args)
  options = args.extract_options!
  fk_options = options.delete(:foreign_key)

  if fk_options && !options[:polymorphic]
    fk_options = {} if fk_options == true
    args.each { |to_table| foreign_key(to_table, fk_options) }
  end

  references_without_foreign_keys(*(args << options))
end

#to_sql_with_foreign_keys ⇒ Object 



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# File 'lib/foreigner/connection_adapters/abstract/schema_definitions.rb', line 76

def to_sql_with_foreign_keys
  sql = to_sql_without_foreign_keys
  sql << ', ' << (foreign_keys * ', ') if foreign_keys.present?
  sql
end