使用用户scott和口令，不加schema,和table，缺省导出的是当前用户scott的模式下的对象

[oracle@yitai test]$ expdp scott/oracle  directory=dir_test dumpfile=scott2.dump logfile=scott2.log              

Export: Release 10.2.0.4.0 - Production on Monday, 11 June, 2012 19:12:22

Copyright (c) 2003, 2007, Oracle.  All rights reserved.

Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Starting "SCOTT"."SYS_EXPORT_SCHEMA_01":  scott/******** directory=dir_test dumpfile=scott2.dump logfile=scott2.log
Estimate in progress using BLOCKS method...
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 256 KB
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/TABLE/TABLE
Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX
Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type SCHEMA_EXPORT/TABLE/COMMENT
Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/REF_CONSTRAINT
Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
. . exported "SCOTT"."DEPT"                              5.656 KB       4 rows
. . exported "SCOTT"."EMP"                               7.820 KB      14 rows
. . exported "SCOTT"."EMP1"                              7.820 KB      14 rows
. . exported "SCOTT"."SALGRADE"                          5.585 KB       5 rows
. . exported "SCOTT"."BONUS"                                 0 KB       0 rows
Master table "SCOTT"."SYS_EXPORT_SCHEMA_01" successfully loaded/unloaded
******************************************************************************
Dump file set for SCOTT.SYS_EXPORT_SCHEMA_01 is:
  /home/oracle/test/scott2.dump
Job "SCOTT"."SYS_EXPORT_SCHEMA_01" successfully completed at 19:12:28