SELECT a.tablespace_name "表空间名", 

total "表空间大小",  free "表空间剩余大小",  (total - free) "表空间使用大小",  total / (1024 * 1024 * 1024) "表空间大小(G)",  free / (1024 * 1024 * 1024) "表空间剩余大小(G)",  (total - free) / (1024 * 1024 * 1024) "表空间使用大小(G)",  round((total - free) / total, 4) * 100 "使用率 %"  FROM (SELECT tablespace_name, SUM(bytes) free  FROM dba_free_space  GROUP BY tablespace_name) a,  (SELECT tablespace_name, SUM(bytes) total  FROM dba_data_files  GROUP BY tablespace_name) b  WHERE a.tablespace_name = b.tablespace_name