Primary Note For Export And Import (Doc ID 1264691.1)

Last updated on AUGUST 25, 2023

Applies to:

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
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.

Details

This article is intended to assist in finding tips and techniques to assist with finding solutions to problems with Export/Import. The document will cover the following topics:

Concepts/Definitions
Diagnosing
Common Solutions
Additional Requests

Actions

Concepts/Definitions

Oracle Export and Import utilities provide a simple way for you to transfer data objects between Oracle databases, even if they reside on platforms with different hardware and software configurations.

When you run Export against an Oracle database, objects (such as tables) are extracted, followed by their related objects (such as indexes, comments, and grants), if any. The extracted data is written to an export dump file.

The Import utility reads the object definitions and table data from the dump file. The new Data Pump utility is not able to read the dumpfile from the Export utility.

Diagnosing

This Primary Note is not intended to be a complete diagnostic guide for the Export or Import utilities. However, a few key articles are listed below.

The Export and Import utilities have not changed significantly since 9.2.x. All messages regarding work in progress, completed, and errors encountered can be written to a log file using the LOG parameter. This log file should be the first place to check for problems with the Export or Import. The Export and Import FAQ <Note 175624.1> documents usage and common issues and defects.

Export and Import are client tools which work under the characterset defined by NLS_LANG. If the characterset defined by NLS_LANG is not a superset of the characterset used by the export tool, it will be necessary for character conversion during the import. There can be issues with character loss in this conversion process.

<Note 48644.1> Identifying the Export Character Set
<Note 15095.1> Export/Import and NLS Considerations
<Note 227332.1> NLS considerations in Import/Export - Frequently Asked Questions
<Note 227337.1> Changing the Database Character Set - Frequently Asked Questions

If export or import appears to be hanging or running slower than expected, refer to <Note 258418.1> for pointers on tracing the process doing the export or import using the 10046 event. Also check hints and tips in <Note 155902.1>.

If experiencing errors when running export or import, search for known issue matching your scenario using the error number(s) starting with the last error and working backwards through the list.

Common Issues

<Note 62427.1> 2Gb or Not 2Gb - File limits in Oracle
<Note 30428.1> Exporting to Tape on Unix System
<Note 230627.1> 9i Export/Import Process for Oracle Applications Release 11i
<Note 305211.1> Very Slow Performance While Import for Particular Table
<Note 739241.1> Import Of A Large Table With A TIMESTAMP Column Is Slow
<Note 727411.1> Database Export slow while exporting triggers – XDB Installed
<Note 729248.1> Conventional & Direct Path Export/Import Are Extremely Slow
<Note 783835.1> Export Slow After Applying 10.2.0.4 Patchset on top of 10.2.0.3