Some practical solutions to impdp Problems

Previously.

Knowledge Point 1: You need to log on to the database and operate create (or replace) directory test_dump as '/opt/test'. test_dump ='/opt/test' cannot be used here ', and/opt/test is enough. You do not need to use/opt/test.

Knowledge Point 2: You do not need to use the same user name as the exported user name during import.

Knowledge Point 3: If "Unable to open the log file." is reported during the import process and test_dump is not found, check the method:

1. First, check whether test_dump is set correctly. You can retrieve the dba_directories table;

2. Check whether the test_dump directory has read and write permissions;

3. You can also check whether the import user has the permission to access dba_directories,

The problem today is that the imported users are normal users and cannot access dba_directories. the first error is "Unable to open the log file. ", cannot find errors such as test_dump, and started to think that there is a problem with test_dump establishment, but dba_directories has a value and the path has read and write permissions, but the imported account does not have the dba_directories permission, certainly, test_dump cannot be read during import. You can use the following two statements to grant the required permissions to this common user:

Grant read, write on directory test_dump to user;

Grant imp_full_database to user;

Knowledge Point 4: Some grant insert... may appear during the import process... an error occurred while granting permissions to an account. It is likely that the imported database does not have a ROLE. If the application does not use this ROLE, ignore it.

Knowledge Point 5: If the imported database contains the structure of the data table to be imported, impdp will fail. It is assumed that the dump of expdp contains DDL statements, so importing data into the database cannot contain the table structure, the table structure of the imported user space needs to be cleared in advance.