Re: [PERFORM] Seeking performance advice and explanation for high I/O on 8.3

[Scott Otis]

Robert Haas <robertmh...@gmail.com>:
 
> Do you by any chance have a bazillion databases in this cluster?  Can
> you do these?

> select sum(1) from pg_database;
 
1555 

> select pg_relation_size('pg_database');
 
221184

> select sum(pg_column_size(d.*)) from pg_database;
 
That gave me:
 
ERROR:  missing FROM-clause entry for table "d"
LINE 1: select sum(pg_column_size(d.*)) from pg_database;

So I did this: 
 
select sum(pg_column_size(d.*)) from pg_database as d;
 
and got:
 
192910
 
Also did this:
 
select sum(pg_database_size(datname)) from pg_database;
 
and got:
 
13329800428 (12.4GB)
 
Scott