这可以很容易地从psql控制台完成。

表大小:\dt+ 数据库大小\l+ 索引大小:\di+

对于表大小，首先使用\c db_name连接数据库。

请注意:上面不会按OP要求的大小排序，但它仍然可以提供帮助。

这将显示模式名、表名、size pretty和size(排序所需)。

SELECT
  schema_name,
  relname,
  pg_size_pretty(table_size) AS size,
  table_size

FROM (
       SELECT
         pg_catalog.pg_namespace.nspname           AS schema_name,
         relname,
         pg_relation_size(pg_catalog.pg_class.oid) AS table_size

       FROM pg_catalog.pg_class
         JOIN pg_catalog.pg_namespace ON relnamespace = pg_catalog.pg_namespace.oid
     ) t
WHERE schema_name NOT LIKE 'pg_%'
ORDER BY table_size DESC;

我基于PostgreSQL数据库中具有大小(相对大小和绝对大小)的模式列表的解决方案来构建它

select table_name, pg_relation_size(quote_ident(table_name))
from information_schema.tables
where table_schema = 'public'
order by 2

如果你有多个模式，这将显示模式公共中所有表的大小，你可能想使用:

select table_schema, table_name, pg_relation_size('"'||table_schema||'"."'||table_name||'"')
from information_schema.tables
order by 3

SQLFiddle示例:http://sqlfiddle.com/#!15/13157/3

手册中所有对象大小函数的列表。

这里的大多数答案使用pg_size_pretty，这是非常有用的，但如果你想输出一个数值，你可以自己计算

SELECT tab_size /1024 AS size_kb
      ,tab_size /1024 /1024 AS size_mb
      ,tab_size /1024 /1024 / 1024 AS size_gb
      ,tab_size /1024 /1024 / 1024 / 1024 AS size_tb
  FROM 
      (
       SELECT pg_total_relation_size(relid) AS tab_size
         FROM pg_catalog.pg_statio_user_tables
        WHERE schemaname = 'your_schema' 
          AND relname = 'your_table'
      ) AS tabs;

SELECT
   relname as "Table",
   pg_size_pretty(pg_total_relation_size(relid)) As "Size",
   pg_size_pretty(pg_total_relation_size(relid) - pg_relation_size(relid)) as "External Size"
   FROM pg_catalog.pg_statio_user_tables ORDER BY pg_total_relation_size(relid) DESC;

从这里截取https://wiki-bsse.ethz.ch/display/ITDOC/Check+size+of+tables+and+objects+in+PostgreSQL+database

如果你正在寻找一个总的分解，吐司和索引大小使用这个:

SELECT *, pg_size_pretty(total_bytes) AS total
, pg_size_pretty(index_bytes) AS INDEX
, pg_size_pretty(toast_bytes) AS toast
, pg_size_pretty(table_bytes) AS TABLE
FROM (
SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes 
FROM (
  SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME
          , c.reltuples AS row_estimate
          , pg_total_relation_size(c.oid) AS total_bytes
          , pg_indexes_size(c.oid) AS index_bytes
          , pg_total_relation_size(reltoastrelid) AS toast_bytes
      FROM pg_class c
      LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
      WHERE relkind = 'r'
  ) a
) a ORDER BY total_bytes DESC;