CiviCRM Community Forums (archive)

Should have triggered a backtrace for you on demo.  database stores a date field as 0 length.  Using a date in dedup w/ non-zero length causes error.I think DOB is a good tool for dedupe....need to either ignore date length or ignore input (prefered.)

https://beta.xxx.com/civicrm/contact/deduperules?action=add&contact_type=Individual&reset=1
Message   $Fatal Error Details = Array ( [callback] => Array (

• => CRM_Core_Error [1] => handle )
  Code: [Select]
  => -1 [message] => DB Error: unknown error [mode] => 16 [debug_info] => CREATE INDEX dedupe_index_birth_date_10 ON civicrm_contact (birth_date(10)) [nativecode=1089 ** Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys] [type] => DB_Error [user_info] => CREATE INDEX dedupe_index_birth_date_10 ON civicrm_contact (birth_date(10)) [nativecode=1089 ** Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys] [to_string] => [db_error: message="DB Error: unknown error" code=-1 mode=callback callback=CRM_Core_Error::handle prefix="" info="CREATE INDEX dedupe_index_birth_date_10 ON civicrm_contact (birth_date(10)) [nativecode=1089 ** Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys]"] )[/li]