查看表大小

col owner format a20
col object_name format a50
set linesize 100
select owner,object_name from dba_objects where owner='ORDDATA' and object_type='TABLE';

col owner format a20
col SEGMENT_NAME format a50
col BYTES format 999999999999
set linesize 100
select OWNER,SEGMENT_NAME,BYTES/1024/1024 from dba_segments where owner='ORDDATA' oder by bytes desc;

col owner format a20
col SEGMENT_NAME format a50
col BYTES format 999999999999
set linesize 100
SELECT owner, segment_name, segment_type, bytes/1024/1024 AS size_mb FROM dba_segments WHERE segment_type = 'TABLE' ORDER BY size_mb DESC;