查询到表空间有个对象占用空间非常大，达200G
SQL> select * from ( 2 select owner,segment_name,tablespace_name,segment_type,bytes/1024/1024 from dba_segments order by 5 desc ) where TABLESPACE_NAME='USERS' AND rownum<20; 3 OWNER SEGMENT_NAME ------------------------------ ----------------------------------- TABLESPACE_NAME SEGMENT_TYPE BYTES/1024/1024 ------------------------------ ------------------ --------------- UNIGUARD SYS_LOB0000052424C00006$$ USERS LOBSEGMENT 204859 UNIGUARD IMAGE_FILE USERS TABLE 10826 UNIGUARD CAR_TRACK_10 USERS TABLE 4097
LOBSEGMENT的系统命名规则是
SYS_LOB(10 digit object_id)C(5 digit col#)$$ 表段
SYS_IL(10 digit object_id)C(5 digit col#)$$ 索引
SQL> select object_name,status from dba_objects where object_id='0000052424'; OBJECT_NAME -------------------------------------------------------------------------------- STATUS ------- IMAGE_FILE VALID
原来是image_file使用了lob字段，为了释放出空间，我把此表导出，重建，再导入。结果空间释放。