hello people... sorry im new with this stuff, cant get it right... i need help...

suppose i have a table that has the stores in columns and and order count as a row:

Store1 Store2 Store3 Store4
ordercount 100 null null 30

assume that there are many stores listed in the table... how can i have the number of stores that has an ordercount?... ive tried some mdx queries but i still cant get it right...