The view column_udt_usage identifies all columns
   that use data types owned by a currently enabled role.  Note that in
   PostgreSQL, built-in data types behave
   like user-defined types, so they are included here as well.  See
   also Section 32.12 for details.
  
Table 32-9. column_udt_usage Columns
| Name | Data Type | Description | 
|---|
| udt_catalog | sql_identifier | Name of the database that the column data type (the underlying
       type of the domain, if applicable) is defined in (always the
       current database) | 
| udt_schema | sql_identifier | Name of the schema that the column data type (the underlying
       type of the domain, if applicable) is defined in | 
| udt_name | sql_identifier | Name of the column data type (the underlying type of the
       domain, if applicable) | 
| table_catalog | sql_identifier | Name of the database containing the table (always the current database) | 
| table_schema | sql_identifier | Name of the schema containing the table | 
| table_name | sql_identifier | Name of the table | 
| column_name | sql_identifier | Name of the column |