Space Planning Multippe Libraries

Hi,
I work for a retail store that has multiple departments and I was wondering which technique to implement is better, either create one big database file with all the product and create a big library out of it OR create a database file for each department and make a library for each department?
What if each department has multiple sub-departments?
In you opinion, what should be the best way to do this?

thanks,

Miguel

Pros of splitting: faster performance and smaller disk space if copied to local drive.
Cons of splitting: difficulty finding a product if you don't know what department it belongs to or misplacing items into wrong library.

I use to work for a large retailer and they split their libraries into departments.

Hi Eric,

Thank you for your fast response. I guess that makes sense when we consider performance time. I don't have experience at all concerning Space Planning, but I am going through the contents of the Help menu while the department authorizes the online training session with JDA.
I am setting up a folder structure in an external NAS that will containg the planograms and the images in different folders, each in its own department. Each department have also its own set of subdepartments, and I know that this can get complicated. For example:
We have 19 departments
The Cosmetics department have 30 subdepartments
The Electric department have 37 subdepartments
The Food General department have 54 subdepartments
The Foto Video department have 5 subdepartments
...

I am going through all this problem because I want to get everything as much organized as possible, so I won't have to deal with this again, and will be much better for me and my team to arrange any changes...call me picky. So far we only have two Space Planning license on two different machines, and I want to set the data source in Space Planning to point to the databases that I will be setting in the folder structure in the NAS.

While I understand databases I still struggling in design one that will fit all my needs. I finished reading the process of creating a product library in Space Planning and I have a few questions about it.

Q1:
Should I create a database for each subdepartment in each department or a single database for department should suffice?

Q2:
In you opinion what database management system should I use: dBase, Access or SQL Server?

(I put dBase in the list because my company still uses a old legacy system to provide its employees with reporting and text files with data that can be latter on imported into a database. The previous person in charge of my position used Virtual FoxPro to do this but never left a manual or guide to follow. This is one of the things that I am trying to change).

Q3:
Can you tell how did you set this up when you worked at the large retailer?

Thx,
Miguel