查询表咋用大小

  SELECT
    SUM(bytes)/1024/1024/1024 AS GB
FROM
    dba_segments
WHERE
    segment_type = 'TABLE';
        

查询所有文件占用大小

SELECT
    ROUND(SUM(bytes) / 1024 / 1024 / 1024, 2) AS "Size in GB"
FROM
    dba_data_files;

查询每个表空间大小

SELECT
    tablespace_name,
    ROUND(SUM(bytes) / 1024 / 1024 / 1024, 2) AS "Size in GB"
FROM
    dba_data_files
GROUP BY
    tablespace_name;

参考文章