pg_namespace
   The catalog pg_namespace stores namespaces.
   A namespace is the structure underlying SQL schemas: each namespace
   can have a separate collection of relations, types, etc. without name
   conflicts.
  
Table 51.32. pg_namespace Columns
| Name | Type | References | Description | 
|---|---|---|---|
| oid | oid | Row identifier | |
| nspname | name | Name of the namespace | |
| nspowner | oid |  | Owner of the namespace | 
| nspacl | aclitem[] | Access privileges; see Section 5.7 for details |