Oracle 21c

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create table inventoryItem (
       itemNum    varchar(10) not null,
       code   varchar(20) not null,
       qtyInstock float       not null,
       itemColor  varchar(15),
       itemSize   float,
       primary key (itemNum, code)
);
begin
insert into inventoryItem values ('A0', 'pbk', 30, 'black', 3.0);
insert into inventoryItem values ('B1', 'hbk', 50, 'white', 4.0);
insert into inventoryItem values ('A0', 'hbk', 25, 'green', 4.0);
insert into inventoryItem values ('C2', 'hbk', 20, 'black', 3.0);
insert into inventoryItem values ('C1', 'ebk', 70, 'black', 4.0);
insert into inventoryItem values ('A3', 'pbk', 30, 'black', 2.0);
insert into inventoryItem values ('A2', 'pbk', 50, 'green', 3.0);
insert into inventoryItem values ('A0', 'ebk', 15, 'green', 4.0);
insert into inventoryItem values ('C2', 'pbk', 30, 'black', 3.0);
end;
/
1 rows affected

SELECT LISTAGG(itemnum, ', ') WITHIN GROUP (ORDER BY itemnum) itemNum,
itemsize, itemcolor, SUM(qtyinstock) qty_of_combination, 
       CASE WHEN cnt <= 1 THEN 'BR-2 Satisifed' ELSE 'BR-2 Violated' END itemNumRules
FROM (SELECT itemnum, itemsize, itemcolor, qtyinstock, 
             COUNT(*) OVER(partition by itemsize, itemcolor) cnt
        FROM inventoryitem)
GROUP BY itemsize, itemcolor, cnt;


ITEMNUM
ITEMSIZE
ITEMCOLOR
QTY_OF_COMBINATION
ITEMNUMRULES


A3
2
black
30
BR-2 Satisifed

A0, C2, C2
3
black
80
BR-2 Violated

A2
3
green
50
BR-2 Satisifed

C1
4
black
70
BR-2 Satisifed

A0, A0
4
green
40
BR-2 Violated

B1
4
white
50
BR-2 Satisifed

ITEMNUM	ITEMSIZE	ITEMCOLOR	QTY_OF_COMBINATION	ITEMNUMRULES
A3	2	black	30	BR-2 Satisifed
A0, C2, C2	3	black	80	BR-2 Violated
A2	3	green	50	BR-2 Satisifed
C1	4	black	70	BR-2 Satisifed
A0, A0	4	green	40	BR-2 Violated
B1	4	white	50	BR-2 Satisifed