Re: Table sizes

Hello

On 2020-09-30 14:11, luis.roberto@siscobra.com.br wrote:
> Hi!
> 
> I'm trying to use this query to get table sizes, however I'm getting a
> strange error:
> 
> select tablename,pg_relation_size(tablename::text)
>   from pg_tables;
> 
> In PG 13:
> 
> SQL Error [42P01]: ERROR: relation "sql_implementation_info" does not
> exist
> 
> In PG 12:
> 
> SQL Error [42P01]: ERROR: relation "sql_parts" does not exist

Try like this:

select schemaname,
        tablename,
        pg_relation_size((schemaname || '.' || '"' || tablename || 
'"')::regclass)
from pg_tables;

You need to schema qualify the tables. Additionally, if you happen to 
have table names that have a mix of capital and non capital letters or 
contain other characters that might be problematic, you need to enclose 
the table name in double quotes.

Regards
Charles

-- 
Charles Clavadetscher
Swiss PostgreSQL Users Group
Treasurer
Spitzackerstrasse 9
CH - 8057 Zürich

http://www.swisspug.org

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