Add columns

Hello Experts, In Adventure_Work file we have "sales territory key" column in the DimGeography table and FactInternationalSales. And the two tables have many to many relationship through this column. How can I add "Geography Key" column from DimGeography table to FactInternationalSales table so there would be a one-to-many relation between DimGeography and factInternationalSales tables through Geography Key column.