NLS_NCHAR_CHARACTERSET 和 NLS_CHARACTERSET

SQL> select * from nls_database_parameters;
 
PARAMETER                                        VALUE
------------------------------------------------ ----------------------------
NLS_LANGUAGE                                     AMERICAN
NLS_TERRITORY                                    AMERICA
NLS_CURRENCY                                     $
NLS_ISO_CURRENCY                                 AMERICA
NLS_NUMERIC_CHARACTERS                           .,
NLS_CHARACTERSET                                 AL32UTF8
NLS_CALENDAR                                     GREGORIAN
NLS_DATE_FORMAT                                  DD-MON-RR
NLS_DATE_LANGUAGE                                AMERICAN
NLS_SORT                                         BINARY
NLS_TIME_FORMAT                                  HH.MI.SSXFF AM
NLS_TIMESTAMP_FORMAT                             DD-MON-RR HH.MI.SSXFF AM
NLS_TIME_TZ_FORMAT                               HH.MI.SSXFF AM TZR
NLS_TIMESTAMP_TZ_FORMAT                          DD-MON-RR HH.MI.SSXFF AM TZR
NLS_DUAL_CURRENCY                                $
NLS_COMP                                         BINARY
NLS_LENGTH_SEMANTICS                             BYTE
NLS_NCHAR_CONV_EXCP                              FALSE
NLS_NCHAR_CHARACTERSET                           AL16UTF16
NLS_RDBMS_VERSION                                10.2.0.4.0

主要需要关心的就是 NLS_NCHAR_CHARACTERSET 和 NLS_CHARACTERSET。

NLS_CHARACTERSET 是 CHAR, VARCHAR2, CLOB 等列的编码。

NLS_NCHAR_CHARACTERSET 是NCHAR, NVARCHAR2, NCLOB等列的编码。