oracle10g - How to export empty tables in oracle

Question

I have a big problem When i take a dump of database the empty tables are truncated

How i can export the all tables in oracle 10g

exp SYSTEM/password FILE=expdat.dmp

Answer 1

This might be because of these tables may not be extent allocated. Before taking backup you need to identify all the tables that do not have data. Then alter these tables to allocate extent.

ALTER TABLE <table_name> ALLOCATE EXTENT;

Use the below script to alter all tables they do not have extent allocated.

SELECT 'ALTER TABLE '||table_name||' ALLOCATE EXTENT;' FROM user_tables WHERE segment_created = 'NO';

Copy the output and execute it.