This module containstwo functions that report the size of a given

databaseor relation. E.g.,

This module containsseveral functions that report the size of a given

databaseobject:

SELECT database_size('template1');

SELECT relation_size('pg_class');

int8 database_size(name)

int8 relation_size(text)

These functions report the actual file system space. Thus, users can

avoid digging through the details of the database directories.

int8 pg_database_size(oid)

int8 pg_tablespace_size(oid)

int8 pg_relation_size(oid)

Copy this directory to contrib/dbsize in your PostgreSQL source tree.

Then just run make; make install. Finally, load the functions into any

database using dbsize.sql.

text pg_size_pretty(int8)

The first two functions:

SELECT database_size('template1');

SELECT relation_size('pg_class');

take the name of the object, and support databases and tables. Please

note that relation_size() only reports table file usage and not the

space used by indexes and toast tables.

Functions using oids are:

SELECT pg_database_size(1); -- template1 database

SELECT pg_tablespace_size(1663); -- pg_default tablespace

SELECT pg_relation_size(1259); -- pg_class table size

pg_relation_size() will report the size of the table, index and toast

table OIDs, but they must be requested individually. To obtain the total

size of a table including all helper files you'd have to do something

like:

XXX This query does not work, syntax error XXX

SELECT pg_relation_size(cl.oid) AS tablesize,

CASE WHEN reltoastrelid=0 THEN 0

ELSE pg_relation_size(reltoastrelid) END AS toastsize,

SUM(pg_relation_size(indexrelid)) AS indexsize,

pg_size_pretty(pg_relation_size(cl.oid)

+ pg_relation_size(reltoastrelid)

+ SUM(pg_relation_size(indexrelid))::int8)

AS totalsize

FROM pg_class cl

JOIN pg_index ON cl.oid=indrelid

WHERE relname = 'pg_rewrite'

GROUP BY 1,2

This sample query utilizes the helper function pg_size_pretty(int8),

which formats the number of bytes into a convenient string using KB, MB,

GB. It is also contained in this module.

To install, just run make; make install. Finally, load the functions

into any database using dbsize.sql.

When computing the size of a table, it does not include TOAST or index

disk space.