Why Oracle displays ??? for special characters like åäö
问题 Some time ago my PL/SQL stopped showing characters åäö . I've tried reinstalling oracle_home_11g, PL/SQL cleaned the registry but the problem remains. Anyone know why? 回答1: Most probably it is due to the mismatch between the locale-specific NLS characterset and the database characterset . Or else, the NLS_LANG value is not correctly set in the OS environmental variable . Have a look at Why are junk values/special characters/question marks displayed on my client? Your client charaterset doesn