Oracle12c更改数据库字符集为ZHS16GBK

查询数据库字符集，将字符集改为ZHS16GBK SQL> select * from nls_database_parameters where parameter='NLS_CHARACTERSET'; PARAMETER -------------------------------------------------------------------------------- VALUE -------------------------------------------------------------------------------- NLS_CHARACTERSET WE8MSWIN1252 SQL> show pdbs     CON_ID CON_NAME  OPEN MODE  RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED  READ ONLY  NO 3 PDB_ORCL  READ WRITE NO SQL> show pdbs          CON_ID CON_NAME  OPEN MODE  RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED  READ ONLY  NO 3 PDB_ORCL  READ WRITE NO 关闭数据库 SQL> shu immediate Database closed. Database dismounted. ORACLE instance shut down. 启动数据库到mount模式 SQL> startup mount ORACLE instance started. Total System Global Area 1.6267E+11 bytes Fixed Size    7653480 bytes Variable Size 2.4159E+10 bytes Database Buffers 1.3798E+11 bytes Redo Buffers  529215488 bytes Database mounted. 限制session并修改相关参数（记住参数值，最后更改完字符集需要将这些参数改成原值） SQL> alter system enable restricted session; System altered. SQL>  show parameter job_queue_processes;  NAME     TYPE ------------------------------------ ---------------------- VALUE ------------------------------ job_queue_processes     integer 1000 SQL> show parameter aq_tm_processes;  NAME     TYPE ------------------------------------ ---------------------- VALUE ------------------------------ aq_tm_processes     integer 1 SQL> alter system set job_queue_processes=0; System altered. SQL> alter database open; Database altered. SQL> alter database character set ZHS16GBK; alter database character set ZHS16GBK * ERROR at line 1: ORA-12712: new character set must be a superset of old character set 出现错误提示，新字符集必须是老字符集的超集，也就原来字符集是新字符集的子集。 使用Oracle内部命令internal_use跳过使用超集检查。 SQL> alter database character set internal_use ZHS16GBK;   alter database character set internal_use ZHS16GBK * ERROR at line 1: ORA-12720: operation requires database is in EXCLUSIVE mode 报错信息要求数据库在EXCLUSIVE模式下，修改集群数据库参数为false（单库不需要调整该参数 ，该参数在修改完字符集之后需要改回原值）并重启数据库 SQL> alter system set cluster_database=FALSE scope=spfile sid='*'; System altered. SQL> shu immediate Database closed. Database dismounted. ORACLE instance shut down. 注意：启动数据库需要启动到restrict模式下，不然在修改字符集的时候可能汇报如下错误： ORA-12719: operation requires database is in RESTRICTED mode SQL> startup restrict ORACLE instance started. Total System Global Area 1.6267E+11 bytes Fixed Size    7653480 bytes Variable Size 2.4159E+10 bytes Database Buffers 1.3798E+11 bytes Redo Buffers  529215488 bytes Database mounted. Database opened. SQL> alter database character set internal_use ZHS16GBK; Database altered. SQL> shu immediate Database closed. Database dismounted. ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 1.6267E+11 bytes Fixed Size    7653480 bytes Variable Size 2.4159E+10 bytes Database Buffers 1.3798E+11 bytes Redo Buffers  529215488 bytes Database mounted. Database opened. 查询修改结果并将上述修改的参数调整为原来的值。 SQL> select * from nls_database_parameters where parameter='NLS_CHARACTERSET';