通过查看监控orabbix，看到一个sql语句，可以查看oracle数据库真实大小。

SELECTto_char(sum(NVL(a.bytes/1024/1024/10-NVL(f.bytes/1024/1024/10,0),0)),'FM99999999999999990')retvalueFROMsys.dba_tablespacesd,(SELECTtablespace_name,sum(bytes)bytesFROMdba_data_filesGROUPBYtablespace_name)a,(SELECTtablespace_name,sum(bytes)bytesFROMdba_free_spaceGROUPBYtablespace_name)fWHEREd.tablespace_name=a.tablespace_name(+)ANDd.tablespace_name=f.tablespace_name(+)ANDNOT(d.extent_managementLIKE'LOCAL'ANDd.contentsLIKE'TEMPORARY')