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DBMS_LOB.SUBSTR Truncates Input After 32764 Characters With Database NLS_CHARACTERSET AL32UTF8 (Doc ID 2563494.1)

Last updated on JULY 25, 2022

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


DBMS_LOB.SUBSTR truncates input after 32764 bytes on a Database with NLS_CHARACTERSET AL32UTF8, 3 bytes are missing while the amount parameter is set as 32767. 

For a database with NLS_CHARACTERSET=AL32UTF8 the dbms_lob.substr returns 32764 bytes.
For a database with NLS_CHARACTERSET=WE8ISO8859P15 the dbms_lob.substr returns 32767 bytes (one byte for each character).
For a database with NLS_CHARACTERSET=UTF8 the dbms_lob.substr returns 32765 characters.


Migrating data from a database with NLS_CHARACTERSET=WE8ISO8859P15 to a database with NLS_CHARACTERSET=AL32UTF8.


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