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您如何找到 Postgres / PostgreSQL 表及其索引的磁盘大小

我从 Oracle 来到 Postgres,并寻找一种方法来根据 bytes/MB/GB/etc 查找表和索引大小,甚至更好地查找所有表的大小。在 Oracle 中,我有一个讨厌的长查询,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,但我没有看到在哪里。


J
JelteF

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() 来包含元数据并使大小相加。


顺便说一句,如果有人有任何关于如何为大而重复的表达别名的信息,我会很高兴听到它。
你不能给它取别名,但你总是可以在子查询中运行它......比如: SELECT table_full_name,pg_size_pretty(size) FROM ( SELECT .. AS table_full_name, .. AS size FROM .... ) x ORDER BY size
一个建议:将 '"' || table_schema || '"."' || table_name || '"' 更改为 format('%I.%I', table_schema, table_name)
如果您希望以编程方式处理原始字节计数(例如用于您自己的 javascript 仪表板),请跳过 pg_size_pretty 并执行内部查询。
C
Community

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 的摘要。)


如果需要同时查看表和索引,\dti+ 可以解决问题。
虽然这返回按名称排序,但最佳答案返回按大小降序排序
S
Skippy le Grand Gourou

如果数据库名称是 snort,下面的句子给出它的大小:

psql -c "\l+ snort" | awk -F "|" '{print $7}'

到目前为止,快速查看大小的最简单答案。我已将其放入 shell 函数 dbsize
此外,您可以将 -t 添加到 psql 命令以避免输出中的列标题(这对自动化很有用),例如:psql -c "\l+ snort" -t | awk -F "|" '{print $7}'
d
daydreamer

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;

G
Greg Smith

PostgreSQL 表具有三个组件: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 有几个示例展示了如何以各种方式滑动和切分可用信息


C
Ciges

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:

仅从“公共”模式中获取表

还显示物化视图数据和索引大小

在物化视图上,我们可以为 refreshing materialized views concurrently 使用索引,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

我认为在 -- 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 属于 information_schema.sql_identifier 类型
U
Uma

检查这个维基。 https://wiki.postgresql.org/wiki/Disk_Usage

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

I
Ibu

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;

请参阅此链接:https://wiki.postgresql.org/wiki/Disk_Usage


A
Anvesh

试试这个脚本来查找所有表大小:

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,请访问此网址:http://www.dbrnd.com/2015/05/how-to-find-size-of-database-and-table-in-postgresql/