Hi, Tom
I need your expertise in this regard. I got 2 tables which contains millions or records. If some certain column is equal (for example, column "id"), then change the target column value of one table to the other one.
For example:

SQL> desc tab1
Name Null? Type
------------------ -------- ----------------------
id NUMBER
new_column NUMBER

SQL> desc tab2
Name Null? Type
------------------ -------- ----------------------
id NUMBER
name NUMBER

I mean we want to change the value of "tab1.new_column" to "tab2.name", if "tab1.id" equals to "tab2.id".
I've tried this, but not quick enough.
SQL> declare
2 CURSOR cur IS
3 select tab2.id,tab2.name
4 from tab1
5 left join tab2 on tab1.id=tab2.id;
6 begin
7 FOR everyRow IN cur
8 loop
9 update tab1
10 set tab1.new_column = everyRow.name
11 where
12 tab1.id = tab2.id;
13 end loop;
14 commit;
15 end;
16 /

What would you likely to do?
Any suggestions please ! ! !