Need Advice - XML or MySQL

Hi folks, Sorry about the long post, please bear with me.

I have a program which I created using Microsoft Excel: http://www.dsm-systems.com/html/screencaps.html

I have been working hard so that the next release of the can be a standalone Windows program, and I've been writing it in Visual Studio 2008 Standard Edition as a Windows Forms program in C#. I'm only learning C# to do this, and have generally been enjoying it a lot.

Unfortunately.....despite trawling the internet and spending $$$ on numerous books for months now, I just can't get my head around saving, retrieving, and editing data on a local hard drive. I can do it with text files, but I don't think they're suitable for my program. I got lost in MSSQL for god only knows how many weeks :( , and my timetable flew out the window quite a while back! I'm still hoping to release Version 2.00 sometime in 2009, although now it will probably be the 4th quarter.

Anyway.....much distress and disappointment eventually led me to www.rentacoder.com . A few days ago I posted a Request for Quote for tuition on the procedures for saving, retrieving, and editing data. I left the type of storage (txt, binary etc) up to the bidder.

I have received two bids at this point.

1. One originally recommended XML until they learned more about my requirements, and are now recommending that they create an instruction video for me on everything from downloading MySQL all the way through using it with C# to achieve my ends.

2. The second also recommended XML and has not changed. He is going to create a sample application using an XML Schema, and powerpoint instruction slides to explain the process.

Neither have submitted a bid price yet.

So......should I go with MySQL or XML ?

I appreciate any advice A LOT! Thankyou.

If those screenshots are what you are attempting to work with, then there is no way you should attempt this with XML. You are going to want to work with primary ids. XML cannot offer you that.

Something else you might want to consider is using SQLite instead of MySQL. This way, you don't have to have a MySQL server running. SQLite is able to read/edit SQLite databases with just a programming library and does not require a server.

Thanks for the response PeeJ. I own the website www.dsm-systems.com. I just posted the link to the screenshots so people could get an idea of where I'm at, but please feel free to look around the rest of the site.

There are 58 categories (Employees, Suppliers, Customers etc) and each category can store up to 50,000 items. The items are stored on worksheets that the user never sees, and the program interacts with the stored data in various ways. That was the previous versions, I'm now moving away from Excel and learning how to re-create the program in C#.

I'll suggest SQLLite to the guy before he bids. Thanks. :)

Just wanted to say thanks for the advice. I got a run down on the pros and cons of MySQL VS SQLLite, and decided to go with MySQL in the end against XML. Hopefully it will work out ok and I'll finally get my head around this. Merry Christmas. L8rs. :)