Depends on the table, There are 'GLOBAL_ATTRIBUTE' columns used for country specific localizations, you can use if you don't have any specific local customizations.It also depends on the table you are looking at as some have more columns. 'OE_ORDER_HEADERS_ALL' vs 'RA_CUSTOMER_TRX_ALL'.
you can register the new table/column using AD_DD api.
pl. visit the followng links.