Question

I want to create a table in my postgres db, with one column which is a multipolgyon. How do i do that?

What i do fails because of this:
undefined method multipolygon for #<ActiveRecord::ConnectionAdapters::PostgreSQLTableDefinition:0x4ac6f70>:

Using this Migration:

class CreateBezirkes < ActiveRecord::Migration
  def change
    create_table :bezirkes do |t|
      t.string :NameK
      t.integer :BezNr
      t.string :Bez_Rz
      t.string :Namek_Num
      t.string :Namek_Rz
      t.string :NameG
      t.string :Label
      t.integer :Bez
      t.integer :District_Code
      t.integer :StatAustria_Bez_Code
      t.integer :StatAustria_Gem_Code
      t.float :Flaeche
      t.float :Umfang
      t.timestamp :Akt_Timestamp
      t.multipolygon :Koordinaten
      t.integer :main_id
    end
    execute <<-SQL
      ALTER TABLE bezirkes
          ADD CONSTRAINT fk_bezirkes_mains
          FOREIGN KEY (main_id)
          REFERENCES mains(id)
    SQL
  end
end

Answer 1

you could use the postgis gem. It is based on Rgeo, which provides some nice spatial methods.

Otherwise just do:

 t.column :koordinaten, :multipolygon

note: your column names should not begin with a capital letter, according to rails conventions.