I am not sure where to report this bug that relates to Drupal Profiles, help appreciated.
This was originally highlighted by another user (snegny) at http://drupal.org/node/116469.
When a new user registers they have certain fields which are presented to them at the point of registration, others can be filled in post-registration. This is configurable within Administer/Profiles.
Regardless of what profile fields are filled in at the point of registration all of the data is put into the 'dru_users' table into the 'data' field, much like the example below.
a:13:{s:13:"profile_fname";s:6:"Sharon";s:13:"profile_sname";s:7:"Smith";s:16:"profile_hometown";s:9:"New York";s:13:"profile_state";s:17:"New York";s:15:"profile_country";s:14:"United States";s:16:"profile_homepage";s:0:"";s:11:"profile_dob";a:3:{s:5:"month";s:1:"8";s:3:"day";s:2:"13";s:4:"year";s:4:"1970";}s:17:"profile_pportrait";s:19:"I live in New York City";s:21:"profile_education_era";s:5:"1970s";s:20:"profile_first_school";s:8:"New York College";s:21:"profile_second_school";s:9:"New York Univeristy";s:15:"profile_college";s:4:"No College";s:7:"contact";i:1;}
At this point you can click on domain.com/country to see members living in the United States and this member will NOT be listed. The reason is that the query for domain/country pulls data from dru_profile_values.