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Alter Database Character Set - Valid Superset Definitions (Doc ID 119164.1)

Last updated on AUGUST 04, 2018

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 8.1.5 to 12.1]
Oracle Database - Enterprise Edition - Version to [Release 12.2]
Information in this document applies to any platform.


This note defines character set combinations which are valid for the
'ALTER DATABASE CHARACTER SET xxxx;' command which can be used in Oracle 8i and 9i.

In Oracle 10g and up the Csalter script needs to be used to do a characterset conversion. Csalter is depending on Csscan to work.
In 10g and 11g the "superset" factor is simply not relevant.

We strongly suggest to ALWAYS use Csscan before doing a characterset change, even if the target is a (strict) superset and you are using 8i / 9i.
<Note 745809.1> Installing and configuring CSSCAN in 10g and 11g
<Note 458122.1> Installing and configuring CSSCAN in 8i and 9i
<Note 444701.1> Csscan output explained

Full, step by step, guides are available for most common conversions in <NOTE 225912.1> Changing the Database Character Set ( NLS_CHARACTERSET )

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