Oracle7 Server Utilities

Export Basics

The concept behind Export's basic function is quite simple: extract the object definitions and table data from an Oracle database and store them in an Oracle-binary format export file that is located typically on tape or on disk. Export files can be used to transfer data between databases that are on machines not connected via a network or as backups in addition to normal backup procedures.

When Export is run against an Oracle database, objects, such as tables, are extracted followed by their related objects, like indexes, comments, and grants, if any, then written to the Export file. See Figure 1 - 1.

Figure 1 - 1. Exporting a Database

Because Export files are saved in Oracle-binary format, export files cannot be read by utilities other than Import. Similarly, Import can read files written by Export, but cannot read files in other formats. If you need to load data from ASCII fixed-format or delimited files, see Part II of this manual for information about SQL*Loader.

File Handling

Export writes export files using the character set specified for the user session; for example, 7-bit ASCII or IBM Code Page 500 (EBCDIC).

Note: Import automatically maps the data to the character set of its host system or to the character set specified for the user session if it is different from that used in the export file.

Additional Information: For the Trusted Oracle7 Server, export files are labeled by the operating system.

See your platform-specific Trusted Oracle7 Server documentation for details about file naming procedures.

Access Privileges

To use Export you must have the CREATE SESSION privilege on an Oracle database. To export tables owned by another user, you must have the EXP_FULL_DATABASE role enabled. This role is granted to all DBAs.

If you do not have the system privileges contained in the EXP_FULL_DATABASE role, you cannot export objects contained in another user's schema.

For example, you cannot export a table in another user's schema, even if you have created a synonym for it.

Displaying the Contents of an Export File

Since files created by Export are stored in Oracle-binary format, they cannot be read by any Oracle7 Server utility or product other than Import.

You can, however, display the contents of an export file by using the Import SHOW option described. In addition, export files can be read only by Import. You cannot use them to transfer data to non-Oracle systems.