Added quadkey column

README.md

@@ -25,6 +25,7 @@ Please add a small reasoning around the following points for each proposed merge
 | floorspace  | float                     |
 | storeys     | integer                   |
 | relation_id | integer                   |
+| quadkey     | char(18)                  |
 
 #### `migrations` - Information about database migrations
 

migrations/00009_add_column_quadkey.sql

+ALTER TABLE public.obm_buildings
+ADD COLUMN IF NOT EXISTS quadkey CHAR(18);