The catalog pg_shdescription stores optional descriptions (comments) for shared database objects. Descriptions can be manipulated with the COMMENT command and viewed with psql's \d commands.
See also pg_description, which performs a similar function for descriptions involving objects within a single database.
Unlike most system catalogs, pg_shdescription is shared across all databases of a cluster: there is only one copy of pg_shdescription per cluster, not one per database.
Table 44-32. pg_shdescription Columns
| Name | Type | References | Description |
|---|---|---|---|
| objoid | oid | any OID column | The OID of the object this description pertains to |
| classoid | oid | pg_class.oid | The OID of the system catalog this object appears in |
| description | text | Arbitrary text that serves as the description of this object |