Suppose I am running multiple column update on one row. Does the database engine physically write new data to the database if some of the columns contain the same values as existed previously in the database? If so, how can it be avoided?
I'm about to implement a job which will run an update on a large table and most of the values will be the same but still, it has to recalculate them all. I am wondering if the update will also rewrite each column even if there is no need to, because the storage media will degrade faster.