wiki Disk Usage, table size: ERROR: could not open relation with OID 0

[Hans Schou]

Hi

I got the message
  ERROR: could not open relation with OID 0
when running the "General Table Size Information" from
https://wiki.postgresql.org/wiki/Disk_Usage

This patch gives some system tables
@@ -12,5 +12,6 @@
           FROM pg_class c
           LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
           WHERE relkind = 'r'
+              AND reltoastrelid!=0
   ) a
 ) a;

But I guess it was supposed to give size of all tables.

I'm running version 9.1.9 so it should be working according to the wiki.

The original statement:

SELECT *, pg_size_pretty(total_bytes) AS total
    , pg_size_pretty(index_bytes) AS INDEX
    , pg_size_pretty(toast_bytes) AS toast
    , pg_size_pretty(table_bytes) AS TABLE
  FROM (
  SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS
table_bytes FROM (
      SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME
              , c.reltuples AS row_estimate
              , pg_total_relation_size(c.oid) AS total_bytes
              , pg_indexes_size(c.oid) AS index_bytes
              , pg_total_relation_size(reltoastrelid) AS toast_bytes
          FROM pg_class c
          LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
          WHERE relkind = 'r'
  ) a) a;


Any help much appreciated.

./best regards