显示特定日期的数据？

Question

  

我正在尝试创建一个需要显示报告的报告系统   每个日期。

  

这些是selected_items 的表格架构   这是stock_list

     

我在后端使用php并在前端使用java来显示   数据。我尝试了几个查询来获得所需的输出但是这样   我无法得到它。这些是我用过的一些问题。

SELECT
   COALESCE(stock_list.date, selected_items.date) AS date,
   SUM( stock_list.qty ) AS StockSum,
   SUM( stock_list.weight ) AS Stockweight,
   COUNT( selected_items.barcode ) AS BilledItems,
   SUM( selected_items.weight ) AS Billedweight
FROM stock_list join selected_items
ON stock_list.date = selected_items.date
GROUP BY COALESCE(stock_list.date, selected_items.date)
ORDER BY COALESCE(stock_list.date, selected_items.date);

  

这给了我前五列，但输出给了我错误的值。   然后我也尝试了Union。

SELECT SUM( qty ) AS StockSum, SUM( weight ) AS Stockweight
FROM  `stock_list` 
WHERE DATE LIKE  '08-Jan-2016'
UNION SELECT COUNT( barcode ) AS BilledItems, SUM( weight ) AS Billedweight
FROM  `selected_items` 
WHERE DATE LIKE  '08-Jan-2016'
UNION SELECT SUM( qty ) AS TotalStock, SUM( weight ) AS TotalWeight
FROM  `stock_list`;

  

这里我得到了四列的正确值，但问题是当我希望它在4列时，＆gt;结果显示在两列中。   任何人都可以指导我，我已经想到了它的java部分，但我不擅长php和mysql。   谢谢

Answer 1

不幸的是，在我尝试执行此查询时，SQL Fiddle崩溃了

SELECT sl.date AS date, B.qtySum AS StockSum, B.weightSum AS Stockweight,
C.barcodeCount AS BilledItems, C.weightSum AS Billedweight
FROM stock_list sl 
JOIN (SELECT SUM(qty) as qtySum, SUM(weight) as weightSum
      FROM STOCK_LIST GROUP BY date) AS B
ON B.date = sl.date
JOIN (SELECT SUM (weight) AS weightSum, COUNT(barcode) AS barcodeCount
      FROM SELECTED_ITEMS GROUP BY date) AS C
ON C.date = sl.date;

As it was tried here。连接的问题是行将连接多次，因此总和会出错。例如，您有四行从第二个表连接，因此总和应该是它的四倍。使用子查询，您可以避免此问题，因为您在加入变量之前对变量进行计数和求和，因此数字应该适合。唉，我无法运行查询，所以我不能100％确定它有效，但它应该是正确的方法。