The two shapefiles available for download are derived from the DGSD database. Both the prefecture shapefile and the county shapefile are time-stamped, and include information about each event of spatial change during the Song dynasty. For entities that did not experience change events, begin dates and end dates default to 0 and 9999 respectively, indicating that they were in existence during the entire dynasty. Please constrain these dates to the beginning and end of the dynasty if you plan to integrate the DGSD with other datasets.
In the shapefile, only one military rank and one civil rank are associated with each prefecture. Market towns (zhen 鎮) and cantons (xiang 鄉) have not been georeferenced, but the number of each are listed as attributes of each county. Prefectures contain most of the demographic data available in the DGSD, with the three kinds of population data (kou 口, ding 丁, and hu 戶) for the three census periods each listed separately.
If you wish to map information about non-Chinese households, state markets, or other attributes; track rank changes; or modify date information, please query the SQL database and create new shapefiles from it.