Oracle 21c

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create table Tmp(
	[Number] VARCHAR2(10)
	,[color] VARCHAR2(50)
)
ORA-00904: : invalid identifier

insert into Tmp(Number,color) values('A','紅、黃');
ORA-00928: missing SELECT keyword

insert into Tmp(Number,color) values('B','黑');
ORA-00928: missing SELECT keyword

insert into Tmp(Number,color) values('C','黑');
ORA-00928: missing SELECT keyword

insert into Tmp(Number,color) values('D','紅、黃、黑');
ORA-00928: missing SELECT keyword

SELECT [Number],NVL([紅],''), NVL([黃],''), NVL([黑],'')
FROM (
	SELECT [Number],[color],'Y' [Agg]
	FROM Tmp
) t 
PIVOT (
	MAX([Agg])
	FOR [color] IN ([紅], [黃], [黑])
) p
ORA-00936: missing expression