sql query in sql server : please explain what this query is actually doing ?



select  u.business_id,u.name, u.cusine,max(u.values1) from SOURCE_DATA u 
unpivot
(
values1 for cusine in (Sandwiches, Pizza, Bars, Food, Mexican, Thai, Indian)

) u where u.values1 = 1 group by u.business_id,u.name, u.cusine order by u.name;