pg_inherits
   The catalog pg_inherits records information about
   table inheritance hierarchies.  There is one entry for each direct
   parent-child table relationship in the database.  (Indirect inheritance can be determined
   by following chains of entries.)
  
Table 52.27. pg_inherits Columns
| Name | Type | References | Description | 
|---|---|---|---|
| inhrelid | oid |  | The OID of the child table | 
| inhparent | oid |  | The OID of the parent table | 
| inhseqno | int4 | If there is more than one direct parent for a child table (multiple inheritance), this number tells the order in which the inherited columns are to be arranged. The count starts at 1. |