update query in oracle

[goodfriend]

I have the following problem:
There are 2 tables which are identical COLA being primary key:-

Table A Table B
---------------- ----------------
COLA COLB COLC COLA COLB COLC
1 ABC XYZ 1 ABC XYZ
2 PQR DEF 2 RPQ FDE

Except that Table A has Changed information which I need to
Sync with Table B at the end of the Day.

I am trying to use SQL to solve the above problem.

IS there anyway in Oracle to execute one SQL and acheive the above, I am aware that finally I can delete the record and reinsert it, however, I would like to do it using a update statement.

I have tried the following without success:
UPDATE B set (COLB, COLC) = ( select COLB, COLC from A where B.COLA = A.COLA )
The above query updates all the rows in table B >:-<

Thanks for all your help.

 

[Cagliostro]

this operation could be a bit complex:

update
(select table_a.colc c1, table_b.colc c2 from Table_A,
Table_B where table_a.cola = table_bcola) x
set c2 = c1

update
(select table_a.colc c1, table_b.colc c2 from Table_A,
Table_B where table_a.cola = table_b.cola) x
set c2 = c1

insert into table_b
(select * from table_a where not cola in (select cola from tableb))

delete from table_b
where not cola in(select cola from table_a)

Ion Filipski

ICQ: 95034075
AIM: IonFilipski
filipski@excite.com

 

[BillDHS]

UPDATE B set (COLB, COLC) = ( select COLB, COLC from A where B.COLA = A.COLA
AND (b.COLB <> A.COLB OR b.COLC <> A.COLC)
)

 

[Rachoor]

UPDATE B
set (COLB, COLC) = (select COLB, COLC
from A
where B.COLA = A.COLA )
where b.cola = (select a.cola
from a
where a.COLA = b.COLA )