在實際開發中經常會遇到計算某個字段的排名的情況
如下表：totak_sales
現在又如此要求：按sales的逆序排序，要求添加一個sales_rank字段，顯示排名順序
方法：
復制代碼 代碼如下:
SELECT a1.Name, a1.Sales, COUNT(a2.sales) Sales_Rank
FROM Total_Sales a1, Total_Sales a2
WHERE a1.Sales <= a2.Sales or (a1.Sales=a2.Sales and a1.Name = a2.Name)
GROUP BY a1.Name, a1.Sales
ORDER BY a1.Sales DESC, a1.Name DESC;
FROM Total_Sales a1, Total_Sales a2
WHERE a1.Sales <= a2.Sales or (a1.Sales=a2.Sales and a1.Name = a2.Name)
GROUP BY a1.Name, a1.Sales
ORDER BY a1.Sales DESC, a1.Name DESC;
結果：
或：
復制代碼 代碼如下:
SELECT a1.Name, a1.Sales, COUNT(a2.sales) Sales_Rank
FROM Total_Sales a1, Total_Sales a2
WHERE a1.Sales < a2.Sales or (a1.Sales=a2.Sales and a1.Name = a2.Name)
GROUP BY a1.Name, a1.Sales
ORDER BY a1.Sales DESC, a1.Name DESC;
FROM Total_Sales a1, Total_Sales a2
WHERE a1.Sales < a2.Sales or (a1.Sales=a2.Sales and a1.Name = a2.Name)
GROUP BY a1.Name, a1.Sales
ORDER BY a1.Sales DESC, a1.Name DESC;
結果：
由上面的方案，我們可以繼續推測，如何選出某項來呢？
比如排名為5的那項內容：
復制代碼 代碼如下:
SELECT * from
(
SELECT a1.Name, a1.Sales, COUNT(a2.sales) Sales_Rank
FROM Total_Sales a1, Total_Sales a2
WHERE a1.Sales < a2.Sales or (a1.Sales=a2.Sales and a1.Name = a2.Name)
GROUP BY a1.Name, a1.Sales
ORDER BY a1.Sales DESC, a1.Name DESC
) as tab WHERE tab.sales_rank=5;
(
SELECT a1.Name, a1.Sales, COUNT(a2.sales) Sales_Rank
FROM Total_Sales a1, Total_Sales a2
WHERE a1.Sales < a2.Sales or (a1.Sales=a2.Sales and a1.Name = a2.Name)
GROUP BY a1.Name, a1.Sales
ORDER BY a1.Sales DESC, a1.Name DESC
) as tab WHERE tab.sales_rank=5;
當然，此時如果將順序修改為3的話，就不能很好的查找到內容了，這個還是一個弊端，需進行修改，待續
以上就是SQL查詢排名函數實例的全部內容，希望能給大家一個參考，也希望大家多多支持服務器之家。
