转载来源 :PostgreSQL 查看数据库,索引,表,表空间大小 : https://www.cnblogs.com/mchina/archive/2013/04/19/3028573.html
一、简介
PostgreSQL 提供了多个系统管理函数来查看表,索引,表空间及数据库的大小,下面详细介绍一下。
二、数据库对象尺寸函数
三、实例讲解
3.1 查看存储一个指定的数值需要的字节数
david=# select pg\_column\_size(1);
pg_column_size
----------------
(1 row)
david=# select pg\_column\_size(10000);
pg_column_size
----------------
(1 row)
david=# select pg\_column\_size('david');
pg_column_size
----------------
(1 row)
david=# select pg\_column\_size('hello,world');
pg_column_size
----------------
(1 row)
david=# select pg\_column\_size('2013-04-18 15:17:21.622885+08');
pg_column_size
----------------
(1 row)
david=# select pg\_column\_size('中国');
pg_column_size
----------------
(1 row)
3.2 查看数据库大小
查看原始数据
david=# \d test
Table "public.test"
Column | Type | Modifiers
-----------+-----------------------+-----------
id | integer |
name | character varying(20) |
gender | boolean |
join_date | date |
dept | character(4) |
Indexes:
"idx\_join\_date\_test" btree (join_date)
"idx\_test" btree (id)
david=# select count(1) from test;
count
---------
(1 row)
查看数据库postgres的oid
# SELECT oid from pg\_database where datname='postgres';
sql语句查询
postgres=# select pg\_size\_pretty(pg\_database\_size('postgres'));
pg_size_pretty
----------------
6229 kB
(1 行记录)
查看david 数据库大小
david=# select pg\_database\_size('david');
pg_database_size
------------------
190534776
(1 row)
查看所有数据库大小
david=# select pg_database.datname, pg\_database\_size(pg_database.datname) AS size from pg_database;
datname | size
-----------+-------------
template0 | 6513156
postgres | 6657144
jboss | 6521348
bugs | 6521348
david | 190534776
BMCV3 | 28147135608
mydb | 10990712
template1 | 6521348
(8 rows)
查看所有数据库大小
david=# select pg_database.datname, pg\_database\_size(pg_database.datname) AS size from pg_database;
这样查出来的结果,看上去太长了,不太容易读数。
3.3 以人性化的方式显示大小
david=# select pg\_size\_pretty(pg\_database\_size('david'));
pg_size_pretty
----------------
MB
(1 row)
索引
创建索引
CREATE INDEX idx_key_eng_search_status
ON base.keyword_engine
USING btree
(search_status);
3.4 查看单索引大小
david=# select pg\_relation\_size('idx\_test');
pg_relation_size
------------------
(1 row)
david=# select pg\_size\_pretty(pg\_relation\_size('idx\_test'));
pg_size_pretty
----------------
MB
(1 row)
david=# select pg\_size\_pretty(pg\_relation\_size('idx\_join\_date\_test'));
pg_size_pretty
----------------
MB
(1 row)
3.5 查看指定表中所有索引大小
david=# select pg\_indexes\_size('test');
pg_indexes_size
-----------------
(1 row)
david=# select pg\_size\_pretty(pg\_indexes\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
idx_test 和idx_join_date_test 两个索引大小加起来差不多等于上面pg_indexes_size() 查询出来的索引大小。
3.6 查看指定schema 里所有的索引大小,按从大到小的顺序排列。
david=# select \* from pg_namespace;
nspname | nspowner | nspacl
--------------------+----------+-------------------------------------
pg_toast | 10 |
pg_temp_1 | 10 |
pg_toast_temp_1 | 10 |
pg_catalog | 10 | {postgres=UC/postgres,=U/postgres}
information_schema | 10 | {postgres=UC/postgres,=U/postgres}
public | 10 | {postgres=UC/postgres,=UC/postgres}
(6 rows)
david=# select indexrelname, pg\_size\_pretty(pg\_relation\_size(relid)) from pg_stat_user_indexes where schemaname='public' order by pg\_relation\_size(relid) desc;
indexrelname | pg_size_pretty
-------------------------------+----------------
idx_join_date_test | 91 MB
idx_test | 91 MB
testtable_idx | 1424 kB
city_pkey | 256 kB
city11 | 256 kB
countrylanguage_pkey | 56 kB
sale_pkey | 8192 bytes
track_pkey | 8192 bytes
tbl_partition_201211_joindate | 8192 bytes
tbl_partition_201212_joindate | 8192 bytes
tbl_partition_201301_joindate | 8192 bytes
tbl_partition_201302_joindate | 8192 bytes
tbl_partition_201303_joindate | 8192 bytes
customer_pkey | 8192 bytes
album_pkey | 8192 bytes
item_pkey | 8192 bytes
tbl_partition_201304_joindate | 8192 bytes
tbl_partition_201307_joindate | 8192 bytes
tbl_partition_201305_joindate | 0 bytes
tbl_partition_201306_joindate | 0 bytes
(20 rows)
查看索引大小
select indexrelname, pg_size_pretty(pg_relation_size(relid)) from pg_stat_user_indexes where schemaname='public' order by pg_relation_size(relid) desc;
3.7 查看指定表大小
david=# select pg\_relation\_size('test');
pg_relation_size
------------------
(1 row)
david=# select pg\_size\_pretty(pg\_relation\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
使用pg_table_size() 函数查看
david=# select pg\_table\_size('test');
pg_table_size
---------------
(1 row)
david=# select pg\_size\_pretty(pg\_table\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
3.8 查看指定表的总大小
david=# select pg\_total\_relation\_size('test');
pg_total_relation_size
------------------------
(1 row)
david=# select pg\_size\_pretty(pg\_total\_relation\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
3.9 查看指定schema 里所有的表大小,按从大到小的顺序排列。
david=# select \* from pg_namespace;
nspname | nspowner | nspacl
--------------------+----------+-------------------------------------
pg_toast | 10 |
pg_temp_1 | 10 |
pg_toast_temp_1 | 10 |
pg_catalog | 10 | {postgres=UC/postgres,=U/postgres}
information_schema | 10 | {postgres=UC/postgres,=U/postgres}
public | 10 | {postgres=UC/postgres,=UC/postgres}
(6 rows)
david=# select indexrelname, pg\_size\_pretty(pg\_relation\_size(relid)) from pg_stat_user_indexes where schemaname='public' order by pg\_relation\_size(relid) desc;
indexrelname | pg_size_pretty
-------------------------------+----------------
idx_join_date_test | 91 MB
idx_test | 91 MB
testtable_idx | 1424 kB
city_pkey | 256 kB
city11 | 256 kB
countrylanguage_pkey | 56 kB
sale_pkey | 8192 bytes
track_pkey | 8192 bytes
tbl_partition_201211_joindate | 8192 bytes
tbl_partition_201212_joindate | 8192 bytes
tbl_partition_201301_joindate | 8192 bytes
tbl_partition_201302_joindate | 8192 bytes
tbl_partition_201303_joindate | 8192 bytes
customer_pkey | 8192 bytes
album_pkey | 8192 bytes
item_pkey | 8192 bytes
tbl_partition_201304_joindate | 8192 bytes
tbl_partition_201307_joindate | 8192 bytes
tbl_partition_201305_joindate | 0 bytes
tbl_partition_201306_joindate | 0 bytes
(20 rows)
3.7 查看指定表大小
david=# select pg\_relation\_size('test');
pg_relation_size
------------------
(1 row)
david=# select pg\_size\_pretty(pg\_relation\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
使用pg_table_size() 函数查看
david=# select pg\_table\_size('test');
pg_table_size
---------------
(1 row)
david=# select pg\_size\_pretty(pg\_table\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
3.8 查看指定表的总大小
david=# select pg\_total\_relation\_size('test');
pg_total_relation_size
------------------------
(1 row)
david=# select pg\_size\_pretty(pg\_total\_relation\_size('test'));
pg_size_pretty
----------------
MB
(1 row)
3.9 查看指定schema 里所有的表大小,按从大到小的顺序排列。
david=# select relname, pg\_size\_pretty(pg\_relation\_size(relid)) from pg_stat_user_tables where schemaname='public' order by pg\_relation\_size(relid) desc;
relname | pg_size_pretty
-------------------------------+----------------
test | 91 MB
testtable | 1424 kB
city | 256 kB
countrylanguage | 56 kB
country | 40 kB
testcount | 8192 bytes
tbl_partition_201302 | 8192 bytes
tbl_partition_201303 | 8192 bytes
person | 8192 bytes
customer | 8192 bytes
american_state | 8192 bytes
tbl_david | 8192 bytes
emp | 8192 bytes
tbl_partition_201212 | 8192 bytes
tbl_partition_201304 | 8192 bytes
tbl_partition_error_join_date | 8192 bytes
tbl_partition_201211 | 8192 bytes
album | 8192 bytes
tbl_partition_201307 | 8192 bytes