postgres查看数据库大小

1. 查看单库大小

   SELECT pg_size_pretty(pg_database_size('数据库名'));

2. 查看所有库大小

   -- 列出所有数据库名称及大小（格式化）
   SELECT
   datname AS "数据库名",
   pg_size_pretty(pg_database_size(datname)) AS "大小"
   FROM pg_database
   ORDER BY pg_database_size(datname) DESC;

3. 查看数据库各个表大小

   -- 查看指定数据库中各表的大小（含索引）
   -- 需先连接到目标数据库执行
   SELECT
   schemaname || '.' || tablename AS "表名",
   pg_size_pretty(pg_total_relation_size(tablename)) AS "总大小（含索引）",
   pg_size_pretty(pg_relation_size(tablename)) AS "数据大小",
   pg_size_pretty(pg_indexes_size(tablename)) AS "索引大小"
   FROM pg_tables
   WHERE schemaname = 'public' -- 指定模式（如public）
   ORDER BY pg_total_relation_size(tablename) DESC;

4. 查看磁盘占用

PostgreSQL 数据默认存储在data_directory目录下，可通过以下命令查看：

sql

-- 查看数据存储目录
SHOW data_directory;

然后通过系统命令（如du）查看目录大小：

bash

运行

# Linux/macOS下查看目录总大小
du -sh /var/lib/postgresql/14/main  -- 替换为实际数据目录