Update a query using two tables

Question

CREATE TABLE T1
FIELD1 VARCHAR2(10),
VALUE1 INTEGER,
FIELD2 VARCHAR2(10),
VALUE2 INTEGER
INSERT INTO T1 VALUES('OLD',100,'NEW',1000);
INSERT INTO T1 VALUES('OLD',200,'NEW',2000);
INSERT INTO T1 VALUES('OLD',300,'NEW',3000);
CREATE TABLE T2
FIELD VARCHAR2(10),
VALUE INTEGER,
NAM VARCHAR2(10)
INSERT INTO T2 VALUES('OLD',100,'ABC');
INSERT INTO T2 VALUES('OLD',200','ABC');
INSERT INTO T2 VALUES('OLD',600,'ABC');
INSERT INTO T2 VALUES('OLD',300,'XYZ');
Currently there are old values in the table T2.But the current requirement is the corresponding new values present in table T1 should get reflected.One more condition is the NAM='ABC'
I am trying to write in this way.It's getting target updated by multiple source rows.Please help in thi sregard.
UPDATE T2 A
SET A.FIELD=B.FIELD2,A.VALUE=B.VALUE2
FROM T1 B INNER JOIN T2 A
ON T2.VALUE=T1.VALUE1
AND T2.NAM='ABC'
Regards
KVB

Answer 1

You need something more like...
UPDATE T2 A
SET (A.FIELD, A.VALUE)=(SELECT B.FIELD2,B.VALUE2
                        FROM   T1 B
                        WHERE  A.VALUE=B.VALUE1)
WHERE T2.NAM='ABC'(untested)