The view view_column_usage identifies all
   columns that are used in the query expression of a view (the
   SELECT statement that defines the view).  A
   column is only included if the current user is the owner of the
   table that contains the column.
  
Note:     Columns of system tables are not included.  This should be fixed
    sometime.
   
Table 31-37. view_column_usage Columns
| Name | Data Type | Description | 
|---|
| view_catalog | sql_identifier | Name of the database that contains the view (always the current database) | 
| view_schema | sql_identifier | Name of the schema that contains the view | 
| view_name | sql_identifier | Name of the view | 
| table_catalog | sql_identifier |        Name of the database that contains the table that contains the
       column that is used by the view (always the current database)
       | 
| table_schema | sql_identifier |        Name of the schema that contains the table that contains the
       column that is used by the view
       | 
| table_name | sql_identifier |        Name of the table that contains the column that is used by the
       view
       | 
| column_name | sql_identifier | Name of the column that is used by the view |