11g Oracle Export table does not export data as null by default
1, oracle11g default to empty table does not assign segment, so use EXP export oracle11g database, empty table will not export.
2, set the Deferred_segment_creation parameter is false, whether it is empty table or Non-empty table, are allocated segment.
In Sqlplus, execute the following command:
Sql>alter system set Deferred_segment_creation=false; View:
Sql>show parameter deferred_segment_creation;
This value is set to work only on the newly added table, which does not affect the previously created empty table.
Solution:
1. Find an empty table using the following sentence and generate an execution command
Select ' ALTER TABLE ' | | table_name| | ' allocate extent; ' from User_tables where num_rows=0;
2. Export the contents of the query results and execute the exported statements.
3. Then use EXP to export the database, you can fully export the database including the empty table.