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DMU Modifies Column Size of CHAR and VARCHAR2 (Doc ID 2149972.1)

Last updated on JANUARY 13, 2020

Applies to:

Database Migration Assistant for Unicode - Version 2.1 and later
Oracle Database - Enterprise Edition - Version and later
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Information in this document applies to any platform.


When Converting databases to Unicode with the DMU.

The DMU is modifying every CHAR and VARCHAR2 column length to "4x (initial column size) BYTE" before conversion and after conversion back to "(initial column size) (initial length semantics)".

When a table with varchar2(10 char) DMU alters the table to varchar2(40 byte) before the conversion and to varchar2(10 char) after the conversion

This is the case even if the columns are with CHAR semantics.


 Converting  Databases to Unicode Character Set with the DMU.


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