I know the basics regarding relational dbs, however I know very little about other database technologies such as Object dbs, xml dbs, etc. I'm really looking for a shove in the right direction and then I can research further.
I'm building a solution whereby a user can enter text (and perhaps rich-text) data. The user can categorise the data any way they want. For example, in a list of quotations, the user could decide to add (on-the-fly) a column called 'Author' and then assign an author to each quote. They could later on decide to add a column called 'Year' and then assign a year to each quote, etc. Eventually, the user will want to sort/categorise the text items according to the previously mentioned attributes such as author or year.
It's a flexible, almost spreadsheet-like, approach to data management, where the data is mostly unstructured text.
My question is, which database technology should I be considering? It doesn't sound particularly suited to relational. Should I be building an XML database and then using node traversal to sort and categorise? An object database?
My apologies if this sounds vague. As I said, I just want a shove in the right direction. I'm prepared to put in the spade work in learning and researching further.