Oracle SQL: Update a table with data from another table

Question

Table 1:

id    name    desc
-----------------------
1     a       abc
2     b       def
3     c       adf

Table 2:

id    na         


        

Answer 1

BEGIN
For i in (select id, name, desc from table2) 
LOOP
Update table1 set name = i.name, desc = i.desc where id = i.id and (name is null or desc is null);
END LOOP;
END;