如何找到 Postgres / PostgreSQL 表及其索引的磁盘大小

我从 Oracle 转到 Postgres，并寻找一种方法来查找表和索引大小：bytes/MB/GB/etc，或者甚至更好的所有表的大小。在 Oracle 中，我有一个令人讨厌的长查询，它查看 user_lobs 和 user_segments 以返回答案。

我假设在 Postgres 中有一些我可以使用的东西information_schema表，但我不知道在哪里。

Try the 数据库对象大小函数 http://www.postgresql.org/docs/current/interactive/functions-admin.html#FUNCTIONS-ADMIN-DBSIZE。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：为了方便起见，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;

我稍微修改了一下就可以使用了pg_table_size()包含元数据并使大小相加。