Error in master table while importing a single table using Oracle DBMS_DATAPUMP

Question

This issue has been found in Oracle 12.2 only. Oracle 12.1 seems OK. I provide everything to reproduce, but you also need to create an Oracle directory. I named it DUMP_DIRECTORY.

We have 2 SQL procedures:

1. EXPORT_TABLE: Export a table.
2. IMPORT_TABLE: Import a table.

First we create a simple table:

create table MY_TABLE as select 1 as my_column from dual;

Secondly we call the export procedure:

call EXPORT_TABLE('MY_EXPORT_JOB', 'DUMP_DIRECTORY', 'file.dat', 'MY_TABLE', 'export.log');

Thirdly we drop the table:

drop table MY_TABLE;

Finally we call the import procedure:

call IMPORT_TABLE('MY_IMPORT_JOB', 'DUMP_DIRECTORY', 'file.dat', 'import.log');

Almost everything seems fine:

• The procedures are successfully executed.
• There are no errors in export.log and import.log.
• The table is correctly imported back.

But there are errors in the import job master table:

select ERROR_COUNT, OBJECT_TYPE_PATH from MY_IMPORT_JOB where ERROR_COUNT > 0;

ERROR_COUNT OBJECT_TYPE_PATH
----------- -------------------------------------------------------------------
          1 SCHEMA_EXPORT/TABLE/TABLE
          1 SCHEMA_EXPORT/TABLE/TABLE

How to fix or avoid these errors?

Here is EXPORT_TABLE procedure:

create or replace procedure EXPORT_TABLE
(
    JOB_NAME varchar2,
    DIRECTORY_NAME varchar2,
    DMP_FILE_NAME varchar2,
    TABLE_NAME varchar2,
    LOG_FILE_NAME varchar2
)
as
begin
    declare
        handle number(24);
    begin
        -- Open the handle
        handle := DBMS_DATAPUMP.open('EXPORT', 'SCHEMA', NULL, JOB_NAME);

        -- Keep master table to be able to use get_status
        DBMS_DATAPUMP.set_parameter(handle, 'KEEP_MASTER', 1);

        -- Configure files
        DBMS_DATAPUMP.add_file(handle, DMP_FILE_NAME, DIRECTORY_NAME);
        DBMS_DATAPUMP.add_file(handle, LOG_FILE_NAME, DIRECTORY_NAME, null, DBMS_DATAPUMP.KU$_FILE_TYPE_LOG_FILE);

        -- Filter on given table names
        DBMS_DATAPUMP.metadata_filter(handle, 'NAME_LIST', ''''||TABLE_NAME||'''', 'TABLE');
        DBMS_DATAPUMP.metadata_filter(handle, 'INCLUDE_PATH_EXPR', '= ''TABLE''');

        DBMS_DATAPUMP.start_job(handle);

        -- Disconnects a user session from a job.
        DBMS_DATAPUMP.detach(handle);
    end;
end;

Here is IMPORT_TABLE procedure:

create or replace procedure IMPORT_TABLE
(
    JOB_NAME varchar2,
    DIRECTORY_NAME varchar2,
    DMP_FILE_NAME varchar2,
    LOG_FILE_NAME varchar2
)
as
begin
    declare
        handle number(24);
    begin
        handle := DBMS_DATAPUMP.open('IMPORT', 'FULL', NULL, JOB_NAME);

        -- Keep master table to be able to use get_status
        DBMS_DATAPUMP.set_parameter(handle, 'KEEP_MASTER', 1);
        DBMS_DATAPUMP.set_parameter(handle, 'METRICS', 1);

        -- Configure files
        DBMS_DATAPUMP.add_file(handle, DMP_FILE_NAME, DIRECTORY_NAME);
        DBMS_DATAPUMP.add_file(handle, LOG_FILE_NAME, DIRECTORY_NAME, null, DBMS_DATAPUMP.KU$_FILE_TYPE_LOG_FILE);

        -- Change default behavior
        DBMS_DATAPUMP.set_parameter(handle, 'TABLE_EXISTS_ACTION', 'REPLACE');

        -- Start the job
        DBMS_DATAPUMP.start_job(handle);

        -- Disconnects a user session from a job.
        DBMS_DATAPUMP.detach(handle);
    end;
end;