我有一个订单表,如:
product|quantity
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例:
bread|3
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我需要一个选择:
row1- bread
row2- bread
row3- bread
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我是这样做的:
SELECT product FROM (
SELECT product FROM order WHERE quantity > 0 UNION ALL
SELECT product FROM order WHERE quantity > 1 UNION ALL
SELECT product FROM order WHERE quantity > 2 UNION ALL
SELECT product FROM order WHERE quantity > 3
) s;
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它很棒.但是他们告诉我最大数量是4.现在我看到了12,32的订单...所以我不知道最大值.
有没有更好的方法来做到这一点?