Using Drupal to create a database frontend

Hi there,

Being relatively new to Drupal i need a push in the right direction. I just migrated a companies' website from plain HTML to a Drupal installation which went quite well. Now i have to create a frontend for an external database such that all entities in that database can be managed. I believe that requires me building a module, but although i have read trough a fair amount of virtual paper i do not quite get it yet.

I would love to achieve a situation in which database entities act like nodes to which comments can be added or on which the taxonomy system can be used, but without the need for redundant data or the merging of the external database with the Drupal database. The database contains about fifteen tables which could be represented by around ten 'nodes'. (Some nodes contain lists). My main question is, what would be the action plan i would have to follow in order to create a flexible GUI which can manage entities in the other database. I.e. listing, creating, altering and removal of entries or for example providing statistics over the content or any other thing you can possibly do with a relational database. It is a PostgreSQL database and i know i can use the database abstraction layer and connect to multiple databases with it, i already know how to do such a thing using PHP without using the Drupal API. But do i need to create new content types or are there modules that will help me with some of the work upon inclusion?

Thank you in advance.