How to open file with .tda.tdz extension ?

Hi all my name is nonacc, I'm .Net C# developer.

I have a problem, I need to open a file with ".tda.tdz" and ".tda" extension.
I already searched everywhere what is the file and how to open it and have not found anything.

I know that the files created in the system temporary table space during the sort phase, and I think it has something to do with mysql.

I'll be happy and thankful if someone would explain to me what these files and how can I open them, if there's software that can open files of this type, or an explanation of how I can do this in c # if its possible.

Thanks ;)