Oracle如何导出空表？

Oracle如何导出空表？

select table_name from user_tables where NUM_ROWS=0;

select 'alter table '||table_name||' allocate extent;' from user_tables where num_rows=0

        把查询结果导出，执行导出的语句

'ALTERTABLE'||TABLE_NAME||'ALLOCATEEXTENT;'-----------------------------------------------------------alter table AQ$_AQ$_MEM_MC_H allocate extent;alter table AQ$_AQ$_MEM_MC_G allocate extent;alter table AQ$_AQ$_MEM_MC_I allocate extent;alter table AQ$_AQ_PROP_TABLE_T allocate extent;alter table AQ$_AQ_PROP_TABLE_H allocate extent;alter table AQ$_AQ_PROP_TABLE_G allocate extent;alter table AQ$_AQ_PROP_TABLE_I allocate extent;alter table AQ$_KUPC$DATAPUMP_QUETAB_T allocate extent;alter table AQ$_KUPC$DATAPUMP_QUETAB_H allocate extent;alter table AQ$_KUPC$DATAPUMP_QUETAB_G allocate extent;alter table AQ$_KUPC$DATAPUMP_QUETAB_I allocate extent;