The Subschema entry allows a program to access a subschema in the Common
  Data Dictionary/Repository under the schema name.

  Format -

   DB subschema-name WITHIN schema-name

      [ FOR database-name ] [ { THRU    } stream-name ]
                            [ { THROUGH }             ] .

  Additional Information (explode) :

• subschema-name
• schema-name
• database-name
• stream-name