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Description of Invalid Zero Length Column (ZLC) (Doc ID 1606284.1)

Last updated on MARCH 20, 2019

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 8.0.6 to 12.1]
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
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.


 The purpose of this article is to describe an invalid length of Zero in a column (ZLC).


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In this Document
 ZLC Definition
 ZLC and SELECT statements
 ZLC and db_block_checking / db_block_check_for_debug
 ZLC cannot be proactively detected
 Workarounds to fix ZLC

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