6
Migrating Using Export/Import

This chapter guides you through the process of migrating an Oracle7 database to Oracle9i using Export/Import. This chapter covers the following topics:

• Basics of Export/Import

• Migrate the Source Database Using Export/Import

  See Also: Oracle9i Database Utilities for detailed information about using the Export and Import utilities.

Basics of Export/Import

To migrate a database using Export/Import, complete the following three basic steps:

1. Export the data from the database you are migrating (the source database). The export physically copies the data to the export dump file.

2. Create the Oracle9i database into which you will import the exported data (the target database).

3. Import the exported data into the new Oracle9i target database.

   See Also: "Choose a Migration Method" and Oracle9i Database Utilities for information that can help you to evaluate the choice of Export/Import for migration.

Export Utility Requirements

To migrate or upgrade a database, use the Export utility shipped with the release of the source database. After the export, the Import utility can copy the data from the export dump file into the target database. The target database must be created and operational before the Import utility can migrate the exported data into the target database.

For example, if you are migrating to release 9.0.1 from release 7.3, then use the Export utility for release 7.3.

Note: If the source Oracle database is earlier than version 6, then first migrate the source database to at least version 6 before proceeding with the export.

Import Utility Requirements

To migrate, upgrade, or downgrade a database, use the Import utility shipped with the release of the target database. For example, if you are migrating to release 9.0.1 from release 7.3, then use the Import utility for release 9.0.1.

Additional Options

Refer to the following sources if you have additional options installed:

• The Trusted Oracle documentation for information about migrating the features of the Trusted Oracle database if you are exporting from, or importing to, a Trusted Oracle database.

• Appendix G, "Migration and Compatibility for Replication Environments" if you are migrating a database system that has Oracle Replication installed.

Migrate the Source Database Using Export/Import

To migrate an Oracle7 or version 6 database using the Export/Import utilities, complete the following steps:

1. Export the source database using the Export utility shipped with the source database. See the source database's server utilities documents for information about using the Export utility on the source database. Both Oracle7 and version 6 database exports can be imported into Oracle9i.

   To ensure a consistent export, make sure the source database is not available for updates during and after the export. If the source database will be available to users for updates after the export, then, prior to making the source database available, put procedures in place to copy the changes made in the source database to the Oracle9i target database after the import is complete.

2. Install the Oracle9i software. Installation is operating system-specific. Installation steps for Oracle9i are covered in your operating system-specific Oracle9i documentation.

3. If the new Oracle9i database will have the same name as the existing source database, then shut down the existing database before creating the new Oracle9i database.

4. Create the Oracle9i target database.

   See Also: Oracle9i Database Administrator's Guide for information about creating an Oracle9i database.

5. Start SQL*Plus in the Oracle9i environment.

6. Connect to the database instance as a user with SYSDBA privileges.

7. Start an Oracle9i database instance using STARTUP.

8. Pre-create tablespaces, users, and tables in the target database to improve space usage by changing storage parameters. When you pre-create tables using SQL*Plus, either run the database in the original database compatibility mode or make allowances for the specific data definition conversions that occur during import.

   Note: If the new Oracle9i database will be created on the same computer as the source database, and you do not want to overwrite the source database datafiles, then you must pre-create the tablespaces and specify IGNORE=Y and DESTROY=N when you import.

9. Use the Oracle9i Import utility to import the objects exported from the source database. Include the LOG parameter to save the informational and error messages from the import session to a file.

   See Also: Oracle9i Database Utilities for a complete description of the Import utility.

10. After the migration, check the import log file for information about which imports of which objects completed successfully and, if there were failures, which failed.

    See Also: Oracle9i Database Utilities and the Oracle9i server README.doc file for error handling information.

11. Use further Import scenarios (see Oracle9i Database Utilities) or SQL scripts that create the source objects to clean up incomplete imports (or possibly to start an entirely new import).

12. If changes are made to the source database after the export, then make sure those changes are propagated to the Oracle9i database prior to making it available to users. See Step 1 for more information.

13. Complete the procedures described in Chapter 8, "After Migrating or Upgrading the Database".