自定義列的多個值

Question

我想每個ID都有2個Custom_Column的值。 我該怎麼做？

示例表：

ID 
1 
2 
3 

實例查詢：

SELECT id, (id*2) as Custom_Value, (id*4) as Custom_Value FROM numbers 

響應：

ID Custom_Value 
1  2 
1  4 
2  4 
2  8 
3  6 
3  12 

Answer 1

使用UNION

SELECT ID, (ID*2) as CustomVal FROM tableNAme 
UNION ALL 
SELECT ID, (ID*4) as CustomVal FROM tableNAme 
ORDER BY ID 

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