ORA-01427 with table alias used in Procedure - oracle

Question

I have the following snippet within a stored procedure:
(Note, this is not the original snippet, but exactly similar to it except that table and column names have been replaced with more generic ones for better understanding as well as to prevent giving out client code.)
UPDATE table_Orders c SET order_type =
(
SELECT 'PE' FROM
table_Orders A,
table_Orders b,
(SELECT DISTINCT order_id, cust_id, order_date FROM table_Orders WHERE shipment_type = 'T' AND order_availability = 'P' AND order_amt > 500
AND cust_category = 'PREMIUM' ) d
WHERE
A.order_id = d.order_id AND A.order_date = d.order_date AND A.cust_id= d.cust_id
AND A.order_id = b.order_id AND A.order_date = b.order_date AND A.cust_id= b.cust_id
AND A.shipment_type = b.shipment_type AND A.order_availability = b.order_availability AND A.product_id <> b.product_id
AND ((A.order_amt > 500 AND b.shipment_amt > 50) OR (A.shipment_amt > 50 AND b.order_amt > 500))
AND A.order_id = c.order_id AND A.order_date = c.order_date AND A.cust_id = c.cust_id
AND A.shipment_type = c.shipment_type AND A.order_availability = c.order_availability AND A.product_id = c.product_id
);
COMMIT;
Now, my issue is that i am getting the error ORA-01427 single-row subquery returns more than one row while executing the procedure. I tried putting the subquery at the end of the statement using an IN clause as below, but even that did not work:
UPDATE table_Orders c SET order_type =
(
SELECT 'PE' FROM
table_Orders A,
table_Orders b
WHERE
A.order_id = d.order_id AND A.order_date = d.order_date AND A.cust_id= d.cust_id
AND A.order_id = b.order_id AND A.order_date = b.order_date AND A.cust_id= b.cust_id
AND A.shipment_type = b.shipment_type AND A.order_availability = b.order_availability AND A.product_id <> b.product_id
AND ((A.order_amt > 500 AND b.shipment_amt > 50) OR (A.shipment_amt > 50 AND b.order_amt > 500))
AND A.order_id = c.order_id AND A.order_date = c.order_date AND A.cust_id = c.cust_id
AND A.shipment_type = c.shipment_type AND A.order_availability = c.order_availability AND A.product_id = c.product_id
AND (A.order_id, A.cust_id, A.order_date) IN
(SELECT DISTINCT order_id, cust_id, order_date FROM table_Orders
WHERE shipment_type = 'T' AND order_availability = 'P' AND order_amt > 500 AND cust_category = 'PREMIUM')
);
COMMIT;
Could someone kindly guide me in the right direction, as to where I'm bungling this up, or how the subquery is already messed up ?
Code With JOIN --> This gives missing right parenthesis at c.product_Id just before the "JOIN" statement
UPDATE table_Orders c SET order_type =
(
SELECT 'PE' FROM
table_Orders A,
table_Orders b
WHERE
A.order_id = d.order_id AND A.order_date = d.order_date AND A.cust_id= d.cust_id
AND A.order_id = b.order_id AND A.order_date = b.order_date AND A.cust_id= b.cust_id
AND A.shipment_type = b.shipment_type AND A.order_availability = b.order_availability AND A.product_id <> b.product_id
AND ((A.order_amt > 500 AND b.shipment_amt > 50) OR (A.shipment_amt > 50 AND b.order_amt > 500))
AND A.order_id = c.order_id AND A.order_date = c.order_date AND A.cust_id = c.cust_id
AND A.shipment_type = c.shipment_type AND A.order_availability = c.order_availability AND A.product_id = c.product_id
JOIN
SELECT DISTINCT order_id, cust_id, order_date FROM table_Orders
WHERE shipment_type = 'T' AND order_availability = 'P' AND order_amt > 500 AND cust_category = 'PREMIUM' d
ON A.order_id = d.order_id AND A.order_date = d.order_date AND A.cust_id= d.cust_id
COMMIT;

Answer 1

The subquery is probably returning more than one row for some c.order_id, c.order_date, c.cust_id, c.shipment_type, c.order_availability, c.product_id
Without knowing your table structure and data it's hard for us to tell.
But you could do something like this:
UPDATE table_Orders c SET order_type = 'PE'
WHERE (c.order_id, c.order_date, c.cust_id, c.shipment_type, c.order_availability, c.product_id) IN
(
SELECT A.order_id, A.order_date, A.cust_id, A.shipment_type, A.order_availability, A.product_id
FROM
table_Orders A,
table_Orders b,
(SELECT DISTINCT order_id, cust_id, order_date FROM table_Orders WHERE shipment_type = 'T' AND order_availability = 'P' AND order_amt > 500
AND cust_category = 'PREMIUM' ) d
WHERE
A.order_id = d.order_id AND A.order_date = d.order_date AND A.cust_id= d.cust_id
AND A.order_id = b.order_id AND A.order_date = b.order_date AND A.cust_id= b.cust_id
AND A.shipment_type = b.shipment_type AND A.order_availability = b.order_availability AND A.product_id <> b.product_id
AND ((A.order_amt > 500 AND b.shipment_amt > 50) OR (A.shipment_amt > 50 AND b.order_amt > 500))
);
COMMIT;
BTW, why don't you use the "JOIN Syntax" ?
UPDATE The same solution but with ANSI join syntax:
UPDATE table_Orders c
SET order_type = 'PE'
WHERE (c.order_id, c.order_date, c.cust_id, c.shipment_type, c.order_availability, c.product_id) IN
(
SELECT A.order_id, A.order_date, A.cust_id, A.shipment_type, A.order_availability, A.product_id
FROM
table_Orders A
JOIN
table_Orders b ON A.order_id = b.order_id AND A.order_date = b.order_date AND A.cust_id= b.cust_id AND A.shipment_type = b.shipment_type AND A.order_availability = b.order_availability AND A.product_id <> b.product_id
JOIN
(SELECT DISTINCT order_id, cust_id, order_date FROM table_Orders WHERE shipment_type = 'T' AND order_availability = 'P' AND order_amt > 500
AND cust_category = 'PREMIUM' ) d ON A.order_id = d.order_id AND A.order_date = d.order_date AND A.cust_id= d.cust_id
WHERE ((A.order_amt > 500 AND b.shipment_amt > 50) OR (A.shipment_amt > 50 AND b.order_amt > 500))
);