postgresql: database size

VCDB=# select pg_database_size(current_database())/1024/1024;
 ?column?
----------
     1607
(1 row)

VCDB=# select pg_size_pretty(pg_database_size( current_database() )) as human_size , pg_database_size (current_database() ) as raw_size;
 human_size |  raw_size
------------+------------
 1607 MB    | 1685410936
(1 row)

VCDB=# select pg_database_size(current_database())/1024/1024/1024 as size_in_gig;

 size_in_gig

-------------

           1

(1 row)

Looking at entire database size

VCDB=# \d pg_database;

    Table "pg_catalog.pg_database"

    Column     |   Type    | Modifiers

---------------+-----------+-----------

 datname       | name      | not null

 datdba        | oid       | not null

 encoding      | integer   | not null

 datcollate    | name      | not null

 datctype      | name      | not null

 datistemplate | boolean   | not null

 datallowconn  | boolean   | not null

 datconnlimit  | integer   | not null

 datlastsysoid | oid       | not null

 datfrozenxid  | xid       | not null

 dattablespace | oid       | not null

 datacl        | aclitem[] |

Indexes:

    "pg_database_datname_index" UNIQUE, btree (datname), tablespace "pg_global"

    "pg_database_oid_index" UNIQUE, btree (oid), tablespace "pg_global"

Tablespace: "pg_global"

VCDB=# select datname, pg_database_size(datname)/1024/1024 as size_in_Megabytes  from pg_database order by 2 desc;

   datname    | size_in_megabytes

--------------+-------------------

 VCDB1        |             21239

 VCDB2        |              3604

 VCDB3        |              1613

 VCDB         |              1607

 VCDB4        |               943

 VCDB5        |               174

 VCDB6        |                34

 VCDB7        |                25

 VCDB8        |                20

 VCDB9        |                18

 VCDB10       |                 7

 VCDB11       |                 7

 template0    |                 6

 template1    |                 6

 VCDB12       |                 6

 VCDB13       |                 5

 postgres     |                 5

(17 rows)

Total database size

select sum(pg_database_size(datname))/1024/1024/1024 as size_in_gig from pg_database;