The country database contains a number of data tables. All these tables have their own customized editor. There are editor for IOTA tables, QSL managers and station addressses. Below we show the data for countries.

All the important fields for a country. Note the Start end End date for the country.

Mappings are used to determine the country and zone for a callsign. With so many changes in the list of countries, DX4WIN determines the country for a callsign using date ranges. The table above shows this information. Also note that 9A was used for country T7 up to the end of 1983. This line is shown in a different color to make you aware that the same prefix was used for a different country.