I have a database with very bad architecture and no one wants to fix anything and i have to work with what i have. So the problem is in the screen

I need to update users connections and also some more fields… The solution which i see is SET ... WHERE AND SET .. WHERE AND SET ... WHERE (and yes, at this point i’m not even sure that it would work). So may be there is more common way to solve this problem?
As long as your values are different records I think you will need to make individual updates.
You could also consider something like this: