if object_id('tempdb..#src') is not null Drop table #src;
if object_id('tempdb..#trg') is not null drop table #trg;
GO

create table #src (id int, type int, value1 nvarchar(20),value2 nvarchar(20))
insert into #src (id,type,value1,value2)  values (10,8,'888',null), (10,8,'777','ccc'), (10,8,'999',null), (111,8,'999',null)

create table #trg (id int, type int, value1 nvarchar(20),value2 nvarchar(20))
insert into #trg (id,type,value1) values (10,8,'111')


select * from #src
select * from #trg

update #trg set
        value1 = #src.value1,
        value2 = #src.value2
    from #trg join #src on #trg.id = #src.id and #trg.type=#src.type;

select * from #trg
GO

-- select * from #src
id          type        value1               value2
----------- ----------- -------------------- --------------------
10          8           888                  NULL
10          8           777                  ccc
10          8           999                  NULL
111         8           999                  NULL

-- select * from #trg
id          type        value1               value2
----------- ----------- -------------------- --------------------
10          8           111                  NULL


-- select * from #trg после update
id          type        value1               value2
----------- ----------- -------------------- --------------------
10          8           888                  ccc