I've been recently initiated into the world of UTF-8 encoding and how it can help me create a database with languages such as Spanish. In my database, I'll need to add some mathematical symbols (such as the infinity sign). Though I could just turn them into html entities via php and str_replace, I'd prefer to keep the actual characters in the database. Doing some research, it seems like by changing the datatype from varchar to nvarchar, my database will be able to handle such characters.

A couple of questions regarding this:

1) If there's data already in the database and I change the column from varchar to nvarchar, will any of the existing characters be messed up?

2) It seems like nvarchar offers much more flexibility than varchar. If my application will need to deal with different languages & mathematical symbols, why wouldn't I want to use nvarchar?

Thanks so much,