SQL Error: ORA-12712: new character set must be a superset of old character set

Question

I want to change character set of oracle database from \'WE8MSWIN1252\' to \'AL32UTF8\'

I tried to execute following steps from the link (http://download.oracle.com/

Answer 1

The Easiest way: (Shutdown neccesary):

First, Connect as sysdba:

sqplus / as sysdba

Next, execute the following script:

alter system set nls_length_semantics=CHAR scope=both;
shutdown;
startup restrict;
alter database character set INTERNAL_USE WE8ISO8859P1;
shutdown;
startup;

It worked for me in a Oracle 12c Standard Two Edition

Taken from: https://www.elblogdelpibe.com/2015/05/como-solucionar-el-error-ora-12899.html (updated URL)