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ODP.NET From ODAC 12c Returns Wrong Value For CLOB When InitialLOBFetchSize Is Set (Doc ID 1669311.1)

Last updated on FEBRUARY 12, 2019

Applies to:

Oracle Data Provider for .NET - Version and later
Information in this document applies to any platform.


When ODP.NET from ODAC 12c (Release 1 and 2 are both affected) is used to select a value from a CLOB column after the property OracleCommand.InitialLOBFetchSize is set to a positive value, the returned string is completely wrong. It seems like some asian characters are returned, so maybe it is an encoding issue.

Only the partly managed provider (that needs the Instant Client native DLLs) is affected. The bug does not happen with the fully managed provider.

Database used to test: Oracle Database 12c Enterprise Edition Release - 64bit Production on Windows 2008 R2 x64.
Client used to test: ODAC 12c Release 1 ( and ODAC 12c Release 2 (, both in x86 and x64 on Windows 7 SP1 x64.




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