It is easy to solve the problem that an empty oracle11g table cannot be exported using exp.

New Feature of oracle11g. When the number of data entries is 0, no segment is assigned, so it cannot be exported.
 
Solution:
 
1. inserting a piece of data (or deleting it again) is a waste of time. Sometimes hundreds of tables are exhausted.
2. Before creating a database
Code:

SQL code
Alter system set deferred_segment_creation = false;
 
Adjust and recreate a table
Neither of them is good.
The following is the ultimate method:
 
First, query which tables are empty:

SQL code
Select table_name from user_tables where NUM_ROWS = 0;
 
 
The following statement is generated using select:
SQL code
Select 'alter table' | table_name | 'allocate extent; 'from user_tables where num_rows = 0
 
Then the following items are generated in the result window:
 
SQL code
Alter table E2USER_STATE allocate extent;
Alter table comment ise_e2user allocate extent;
Alter table into ise_info_type allocate extent;
Alter table comment ise_mapmark allocate extent;
Alter table paiise_needtask allocate extent;
Alter table comment ise_picture allocate extent;
Alter table paiise_report allocate extent;
Alter table comment ise_report_type allocate extent;
Alter table paiise_team allocate extent;
Alter table FROMUSER_ADJUNCT_TARGET allocate extent;
Alter table FROMUSER_OFFER allocate extent;
Alter table NEEDTASK_TYPE allocate extent;
Alter table SYS_PRIVILEGE allocate extent;
Alter table SYS_RELEVANCE_RESOURCE allocate extent;
Alter table SYS_RELEVANCE_TARGET allocate extent;
Alter table SYS_RESOURCE_TYPE allocate extent;
Alter table TASK_FEEDBACK allocate extent;
Alter table TASK_MYTASKTYPE allocate extent;
Alter table TOUSER_MESSAGE allocate extent;
Alter table ABOUTUSER_POINT allocate extent;
Alter table ABOUTUSER_POINT_MARK allocate extent;
Alter table ABOUTUSER_QUERYKEY allocate extent;
Alter table ABOUTUSER_REPORT_HISTORY allocate extent;
Alter table DICT_COMMENT_TYPE allocate extent;
Alter table DICT_INDUSTRY_TYPE allocate extent;
Alter table DICT_POST allocate extent;
Alter table DICT_REGION allocate extent;
Alter table comment ise_comment allocate extent;
Alter table comment ise_comment_c allocate extent;
Alter table comment ise_info allocate extent;
Alter table paiise_info_c allocate extent;
Alter table into ise_info_state allocate extent;
Alter table CALENDAR_CREATETYPE allocate extent;
Alter table CALENDAR_MY allocate extent;
Alter table CALENDAR_TYPE allocate extent;
 
 
 
OK, execute the preceding SQL statements, and then execute exp, which is a witness to the miracle.

Author: "Sleepless night"