查看表空间的使用情况

SELECT a.tablespace_name "表空间名",
       total / 1024 / 1024 "表空间大小(M)",
       free / 1024 / 1024 "表空间剩余大小(M)",
       (total - free) / 1024 / 1024 "表空间使用大小(M)",
       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