Multiple row update ina table from another table

Hi,

I have the foll schema.

table1:
*P,A,B,C

table2:
*P,A,B,C

Consider the records in the table:
table1:
P A B C
1 x y n
2 x y n
3 x y n
4 p q y
5 p q n

table2:
P A B C
1 x y y
2 p q y

i need to update the field C in table1 with the filed C in table 2
where table1.A = table2.A and table1.B = table2.B.

the foll query is not working.
update table1 t1
set c=
(select t2.c
from table2 t2
where t1.A = t2.A
and t1.B = t2.B
)
where exists
(select t2.c
from table2 t2
where t1.A = t2.A
and t1.B = t2.B
)

pls help meCan you describe "not working" in more detail? Based on the test data that you've posted, there is nothing for the query to do, but it should do nothing quite nicely.

If you change the values of table1.c to 'X' or something like that, then re-run your query, it should put you right back where you started.

-PatP