My Oracle Support Banner

Why Can an Object Not Be Exported? Expdp of SYSTEM User's Table Returns ORA-39166 or ORA-31655 (Doc ID 2114233.1)

Last updated on JANUARY 15, 2024

Applies to:

Oracle Database - Standard Edition - Version and later
Oracle Database - Enterprise Edition - Version to [Release 9.2]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Information in this document applies to any platform.


This document explains why certain objects cannot be exported, and how to find those objects.

There are certain system generated schemas that are not exportable using exp or expdp because they contain Oracle-managed data and metadata. SYS, MDSYS, and ORDSYS are some examples.

In addition, there are other tables owned by users such as SYS or APEX_040200 which are automatically skipped during export, nor can those be exported intentionally.

For example, certain tables owned by SYSTEM user like below cannot be exported:

% expdp system/<PASSWORD> directory=<DIRECTORY_NAME> tables='<TABLE_NAME>'

Export: Release - Production on Thu Mar 3 20:39:27 2016

Copyright (c) 1982, 2014, Oracle and/or its affiliates. All rights reserved.

Connected to: Oracle Database 12c Enterprise Edition Release - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options
Starting "SYSTEM"."SYS_EXPORT_TABLE_01": system/******** directory=<DIRECTORY_NAME> tables='<TABLE_NAME>'
Estimate in progress using BLOCKS method...
Total estimation using BLOCKS method: 0 KB
ORA-39166: Object SYSTEM.<TABLE_NAME> was not found or could not be exported or imported.
ORA-31655: no data or metadata objects selected for job
Job "SYSTEM"."SYS_EXPORT_TABLE_01" completed with 2 error(s) at Thu Mar 3 20:39:31 2016 elapsed 0 00:00:03



To view full details, sign in with your My Oracle Support account.

Don't have a My Oracle Support account? Click to get started!

In this Document

My Oracle Support provides customers with access to over a million knowledge articles and a vibrant support community of peers and Oracle experts.