我从 Oracle 来到 Postgres，并寻找一种方法来查找表和索引大小，以 bytes/MB/GB/etc 为单位，甚至更好地查找所有表的大小。在 Oracle 中，我有一个令人讨厌的长查询，它查看了 user_lobs 和 user_segments 以给出答案。
我假设在 Postgres 中有一些我可以在 information_schema 表中使用的东西，但我不知道在哪里。
【问题讨论】：
标签： postgresql
试试这个：（索引大小/使用统计）
SELECT
t.tablename,
indexname,
c.reltuples AS num_rows,
pg_size_pretty(pg_relation_size(quote_ident(t.tablename)::text)) AS table_size,
pg_size_pretty(pg_relation_size(quote_ident(indexrelname)::text)) AS index_size,
CASE WHEN indisunique THEN 'Y'
ELSE 'N'
END AS UNIQUE,
idx_scan AS number_of_scans,
idx_tup_read AS tuples_read,
idx_tup_fetch AS tuples_fetched
FROM pg_tables t
LEFT OUTER JOIN pg_class c ON t.tablename=c.relname
LEFT OUTER JOIN
( SELECT c.relname AS ctablename, ipg.relname AS indexname, x.indnatts AS number_of_columns, idx_scan, idx_tup_read, idx_tup_fetch, indexrelname, indisunique FROM pg_index x
JOIN pg_class c ON c.oid = x.indrelid
JOIN pg_class ipg ON ipg.oid = x.indexrelid
JOIN pg_stat_all_indexes psai ON x.indexrelid = psai.indexrelid )
AS foo
ON t.tablename = foo.ctablename
WHERE t.schemaname='public'
ORDER BY 1,2;
【讨论】：
如果数据库名称是snort，下面这句话给它大小：
psql -c "\l+ snort" | awk -F "|" '{print $7}'
【讨论】：
dbsize。
-t 添加到psql 命令以避免输出中出现列标题（这对自动化很有用），例如：psql -c "\l+ snort" -t | awk -F "|" '{print $7}'
试试Database Object Size Functions。一个例子：
SELECT pg_size_pretty(pg_total_relation_size('"<schema>"."<table>"'));
对于所有表格，大致如下：
SELECT
table_schema || '.' || table_name AS table_full_name,
pg_size_pretty(pg_total_relation_size('"' || table_schema || '"."' || table_name || '"')) AS size
FROM information_schema.tables
ORDER BY
pg_total_relation_size('"' || table_schema || '"."' || table_name || '"') DESC;
编辑：为方便起见，这是@phord 提交的查询：
SELECT
table_name,
pg_size_pretty(table_size) AS table_size,
pg_size_pretty(indexes_size) AS indexes_size,
pg_size_pretty(total_size) AS total_size
FROM (
SELECT
table_name,
pg_table_size(table_name) AS table_size,
pg_indexes_size(table_name) AS indexes_size,
pg_total_relation_size(table_name) AS total_size
FROM (
SELECT ('"' || table_schema || '"."' || table_name || '"') AS table_name
FROM information_schema.tables
) AS all_tables
ORDER BY total_size DESC
) AS pretty_sizes;
我对其稍作修改以使用 pg_table_size() 以包含元数据并使大小相加。
【讨论】：
'"' || table_schema || '"."' || table_name || '"'改成format('%I.%I', table_schema, table_name)。
pg_size_pretty，如果您希望以编程方式处理原始字节数，例如用于您自己的javascript仪表板，只需执行内部查询。
仅供参考，我从@aib 得到了很好的答案，并对其进行了一些修改：
在物化视图上，我们可以使用refreshing materialized views concurrently 的索引，这允许在更新时使用它们。
好吧，我的查询将如下：
SELECT
table_name,
pg_size_pretty(table_size) AS table_size,
pg_size_pretty(indexes_size) AS indexes_size,
pg_size_pretty(total_size) AS total_size
FROM (
SELECT
table_name,
pg_table_size(table_name) AS table_size,
pg_indexes_size(table_name) AS indexes_size,
pg_total_relation_size(table_name) AS total_size
FROM (
-- tables from 'public'
SELECT table_name
FROM information_schema.tables
where table_schema = 'public' and table_type = 'BASE TABLE'
union
-- materialized views
SELECT oid::regclass::text as table_name
FROM pg_class
WHERE relkind = 'm'
order by table_name
) AS all_tables
-- ORDER BY total_size DESC
order by table_name
) AS pretty_sizes
【讨论】：
-- tables from 'public' 子查询中，table_name 需要转换为文本。进行更改后，该查询对我有用。没有它，我会在 pg_table_size 函数上得到一个泛型类型错误。 table_name 的类型为 information_schema.sql_identifier
下面的查询将为您服务
SELECT nspname || '.' || relname AS "relation",
pg_size_pretty(pg_total_relation_size(C.oid)) AS "total_size"
FROM pg_class C
LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace)
WHERE nspname NOT IN ('pg_catalog', 'information_schema')
AND C.relkind <> 'i'
AND nspname !~ '^pg_toast'
ORDER BY pg_total_relation_size(C.oid) DESC
LIMIT 20;
【讨论】：
【讨论】：
试试这个脚本来查找所有表格大小：
SELECT
table_schema || '.' || table_name AS TableName,
pg_size_pretty(pg_total_relation_size('"' || table_schema || '"."' || table_name || '"')) AS TableSize
FROM information_schema.tables
ORDER BY
pg_total_relation_size('"' || table_schema || '"."' || table_name || '"') DESC
有关在 PostgreSQL 中查找大小的其他不同脚本，请访问以下网址： http://www.dbrnd.com/2015/05/how-to-find-size-of-database-and-table-in-postgresql/
【讨论】：
显示数据库大小：
\l+
例如
=> \l+
berbatik_prd_commerce | berbatik_prd | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | 19 MB | pg_default |
berbatik_stg_commerce | berbatik_stg | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | 8633 kB | pg_default |
bursasajadah_prd | bursasajadah_prd | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | 1122 MB | pg_default |
显示表格大小：
\d+
例如
=> \d+
public | tuneeca_prd | table | tomcat | 8192 bytes |
public | tuneeca_stg | table | tomcat | 1464 kB |
仅适用于psql。
（@zkutch's answer的总结。）
【讨论】：
\dti+ 可以解决问题。
PostgreSQL 表具有三个组成部分：表本身、其上的任何索引以及可能的 TOAST 数据。 http://wiki.postgresql.org/wiki/Disk_Usage
【讨论】：