title: How is sharepoint list data structured?
body: <p>I am curious about how sharepoint stores its list data. 
  From what I know, a list can have dynamic column numbers and you can even change the data type of a column after a list is created. How does sharepoint do this ?</p>
  
  <p>I am asking because I have to create a structure to store some data. But the number of columns of these data is very likely to be changed in the future. I think I can draw something from sharepoint's list database design.</p>
  
  <p>Thanks for you help.</p>