55.19. pg_description
 The catalog pg_description stores optional descriptions (comments) for each database object. Descriptions can be manipulated with the COMMENT command and viewed with psql's \d commands. Descriptions of many built-in system objects are provided in the initial contents of pg_description. 
 See also pg_shdescription, which performs a similar function for descriptions involving objects that are shared across a database cluster. 
Table 55.19. pg_description Columns
Column Type Description  | 
|---|
 The OID of the object this description pertains to  | 
 The OID of the system catalog this object appears in  | 
  For a comment on a table column, this is the column number (the   | 
 Arbitrary text that serves as the description of this object  |