OCP-1Z0-053-V13.02-127题

127.The application tables owned by the user TEST in a test database need to be exported to the APPS

schema in the production database by using Data Pump. Which option of Data Pump Import would you

use to accomplish this?

A. owner

B. touser

C. attach

D. remap_schema

Answer: D

答案解析：

参考：http://docs.oracle.com/cd/E11882_01/server.112/e22490/dp_import.htm#SUTIL3187

REMAP_SCHEMA

Default: There is no default

Purpose

Loads all objects from the source schema into a target schema.

Syntax and Description

REMAP_SCHEMA=source_schema:target_schema

Multiple REMAP_SCHEMA lines can be specified, but the source schema must be different for each one. However, different source schemas can map to the same target schema. The mapping may not be 100 percent complete, because there are certain schema references that Import is not capable of finding. For example, Import will not find schema references embedded within the body of definitions of types, views, procedures, and packages.

If the schema you are remapping to does not already exist, then the import operation creates it, provided that the dump file set contains the necessary CREATEUSER metadata for the source schema, and provided that you are importing with enough privileges. For example, the following Export commands create dump file sets with the necessary metadata to create a schema, because the user SYSTEM has the necessary privileges:

> expdp system SCHEMAS=hr

Password:

password

 

> expdp system FULL=YES

Password:

password

If your dump file set does not contain the metadata necessary to create a schema, or if you do not have privileges, then the target schema must be created before the import operation is performed. This is because the unprivileged dump files do not contain the necessary information for the import to create the schema automatically.

If the import operation does create the schema, then after the import is complete, you must assign it a valid password to connect to it. The SQL statement to do this, which requires privileges, is:

SQL> ALTER USER schema_name IDENTIFIED BY new_password

Restrictions

• Unprivileged users can perform schema remaps only if their schema is the target schema of the remap. (Privileged users can perform unrestricted schema remaps.)

• For example, SCOTT can remap his BLAKE's objects to SCOTT, but SCOTT cannot remap SCOTT's objects to BLAKE.

Example

Suppose that, as user SYSTEM, you execute the following Export and Import commands to remap the hr schema into the scott schema:

> expdp system SCHEMAS=hr DIRECTORY=dpump_dir1 DUMPFILE=hr.dmp

 

> impdp system DIRECTORY=dpump_dir1 DUMPFILE=hr.dmp REMAP_SCHEMA=hr:scott

In this example, if user scott already exists before the import, then the Import REMAP_SCHEMA command will add objects from the hr schema into the existingscott schema. You can connect to the scott schema after the import by using the existing password (without resetting it).

If user scott does not exist before you execute the import operation, then Import automatically creates it with an unusable password. This is possible because the dump file, hr.dmp, was created by SYSTEM, which has the privileges necessary to create a dump file that contains the metadata needed to create a schema. However, you cannot connect to scott on completion of the import, unless you reset the password for scott on the target database after the import completes.