1 SELECT UPPER(F.TABLESPACE_NAME) TABLESPACE_NAME, --  表空间名,
 2        D.TOT_GROOTTE_MB TOT_GROOTTE_MB, --   表空间大小(G),
 3        D.TOT_GROOTTE_MB - F.TOTAL_BYTES USEDMB, ---已使用空间(G),
 4        TO_CHAR(ROUND((D.TOT_GROOTTE_MB - F.TOTAL_BYTES) / D.TOT_GROOTTE_MB * 100,
 5                      2),
 6                ‘990.99‘) || ‘%‘ USAGERATIO, -- 使用比,
 7        F.TOTAL_BYTES, -- 空闲空间(G),
 8        D.MAXBYTES --表空间最大能扩到多大
 9   FROM (SELECT TABLESPACE_NAME,
10                ROUND(SUM(BYTES) / (1024 * 1024 * 1024), 3) TOTAL_BYTES,
11                ROUND(MAX(BYTES) / (1024 * 1024 * 1024), 3) MAX_BYTES
12           FROM SYS.DBA_FREE_SPACE
13          GROUP BY TABLESPACE_NAME) F,
14        (SELECT DD.TABLESPACE_NAME,
15                ROUND(SUM(DD.BYTES) / (1024 * 1024 * 1024), 3) TOT_GROOTTE_MB,
16                ROUND(DD.MAXBYTES / (1024 * 1024 * 1024), 3) MAXBYTES
17           FROM SYS.DBA_DATA_FILES DD
18          GROUP BY DD.TABLESPACE_NAME, DD.MAXBYTES) D
19  WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME
20  ORDER BY 2 DESC

查询表空间所有相关信息sql：select * from dba_data_files;

dba_data_files视图字段说明