select해서 update

update tableA set
addr = (select addr from tableB where usr_nm='홍길동')

update tabeA a set
addr = (select addr from tableB where usr_nm = a.usr_nm)
where 
usr_nm in 
(
  select usr_no from tableB 
)

예시

update tableA AS a set
addr = b.addr
from tableB AS b
where
a.usr_no = b.usr_no