method

remove_foreign_key

v4.2.7 - Show latest stable - Class: ActiveRecord::ConnectionAdapters::SchemaStatements

remove_foreign_key(from_table, options_or_to_table = {})

public

Removes the given foreign key from the table.

Removes the foreign key on accounts.branch_id.

remove_foreign_key :accounts, :branches

Removes the foreign key on accounts.owner_id.

remove_foreign_key :accounts, column: :owner_id

Removes the foreign key named special_fk_name on the accounts table.

remove_foreign_key :accounts, name: :special_fk_name

# File activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb, line 793
      def remove_foreign_key(from_table, options_or_to_table = {})
        return unless supports_foreign_keys?

        if options_or_to_table.is_a?(Hash)
          options = options_or_to_table
        else
          options = { column: foreign_key_column_for(options_or_to_table) }
        end

        fk_name_to_delete = options.fetch(:name) do
          fk_to_delete = foreign_keys(from_table).detect {|fk| fk.column == options[:column].to_s }

          if fk_to_delete
            fk_to_delete.name
          else
            raise ArgumentError, "Table '#{from_table}' has no foreign key on column '#{options[:column]}'"
          end
        end

        at = create_alter_table from_table
        at.drop_foreign_key fk_name_to_delete

        execute schema_creation.accept(at)
      end

remove_foreign_key

Related methods