Trouble moving a Wordpress/CiviCRM install to a subdomain
The instructions for moving an installation should work even though you are only changing the base_url: see http://wiki.civicrm.org/confluence/display/CRMDOC/Moving+an+Existing+Installation+to+a+New+Server+or+Location.

We tend to truncate tables rather than exclude on backup and migrate so that the structure is migrated.

You may be able to check the mysql log (see my.cnf for its location) for the specific table.field that is missing, if you want to try to fix the database you are currently working on. Wild guess: it is custom field, which are stored in the civicrm_value* tables, and defined in the civicrm_custom_field and civicrm_custom_group tables.