ORA Error Codes

Invalid character set specified

Cannot ALTER DATABASE CHARACTER SET when CLOB data exists

Cannot ALTER DATABASE NATIONAL CHARACTER SET when NCLOB data exists

Operation requires connection as SYS

Operation requires database is in RESTRICTED mode

Operation requires database is in EXCLUSIVE mode

Operation cannot execute when other sessions are active

This CREATE DATABASE character set is not allowed

System appears too busy for parallel query execution

Error while getting create database NLS parameter string