Question

我正在尝试获取所有尺寸，并将结果作为GROUP_CONCAT()内的结果。

如果GROUP_CONCAT()内有相同的结果，我们可以使用SUM()
如果NULL或其他大小的product_size.Size_Name那么这个SUM()没有得到SELECT product_table.Product_Name, SUM(product_quantity.Quantity) AS 'QUANTITY', GROUP_CONCAT( product_quantity.Quantity, ' box/es ', product_size.Size_Name, ' size' SEPARATOR '\n' ) AS 'SIZE' FROM product_quantity RIGHT JOIN product_table ON product_quantity.Product_ID = product_table.Product_ID LEFT JOIN product_size ON product_quantity.Size_ID = product_size.size_ID GROUP BY product_table.Product_Name ASC。

顺便说一下，这是我的问题：

  PRODUCT                 QUANTITY                       SIZE

Hawaiian Pizza                 11                   2 - box/es Large size
                                                    3 - box/es Large size
                                                    1 - box/es Small size
                                                    5 - box/es Large size

所以这就是结果：

  PRODUCT                    QUANTITY                       SIZE

Hawaiian Pizza                 11                   10 - box/es Large size
                                                    1 - box/es Small size

这是我现在想要得到的正确答案：

        CREATE TABLE `product_table` (
          `Product_ID` int(40) NOT NULL,
          `Product_Name` varchar(400) NOT NULL
        ) ENGINE=InnoDB DEFAULT CHARSET=latin1;


        INSERT INTO `product_table` (`Product_ID`, `Product_Name`) VALUES
        (1001, 'Hawaiian Pizza'),
        (1002, 'Chicken Alfredo'),
        (1003, 'Chicken Quesadillas'),
        (1004, 'Mexican Pizza'),
        (1006, 'Beef Pepperoni Pizza');

      ALTER TABLE `product_table`
      ADD PRIMARY KEY (`Product_ID`),
      ADD KEY `Product_ID` (`Product_ID`);

      ALTER TABLE `product_table`
       MODIFY `Product_ID` int(40) NOT NULL AUTO_INCREMENT,     
       AUTO_INCREMENT=1007;

但是怎么样？任何想法???

顺便说一下，这是我的表结构：

有关，

表产品：

        CREATE TABLE `product_size` (
          `Size_ID` int(100) NOT NULL,
          `Size_Name` varchar(50) NOT NULL
        ) ENGINE=InnoDB DEFAULT CHARSET=latin1;

        INSERT INTO `product_size` (`Size_ID`, `Size_Name`) VALUES
         (1, 'Small'),
         (2, 'Medium'),
         (3, 'Extra Large'),
         (4, 'Large');

       ALTER TABLE `product_size`
       ADD PRIMARY KEY (`Size_ID`);

       ALTER TABLE `product_size`
       MODIFY `Size_ID` int(100) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=9;

table product_size：

       CREATE TABLE `product_quantity` (
          `Quantity_ID` int(100) NOT NULL,
          `Quantity` int(100) NOT NULL,
          `Product_ID` int(100) NOT NULL,
          `Size_ID` int(100) NOT NULL
        ) ENGINE=InnoDB DEFAULT CHARSET=latin1;

        INSERT INTO `product_quantity` (`Quantity_ID`, `Quantity`, 
       `Product_ID`, `Size_ID`) VALUES
        (18, 2, 1002, 3),
        (19, 1, 1001, 2),
        (20, 2, 1003, 1),
        (21, 3, 1002, 2),
        (22, 1, 1002, 3),
        (23, 2, 1003, 3),
        (24, 3, 1004, 4),
        (25, 1, 1003, 3),
        (26, 3, 1006, 3),
        (27, 4, 1002, 3),
        (28, 2, 1004, 4),
        (29, 4, 1002, 3),
        (30, 2, 1002, 3),
        (31, 2, 1002, 2),
        (32, 3, 1003, 3),
        (33, 23, 1002, 4);

        ALTER TABLE `product_quantity`
        ADD PRIMARY KEY (`Quantity_ID`),
        ADD KEY `Product_ID` (`Product_ID`),
        ADD KEY `Size_ID` (`Size_ID`);

        ALTER TABLE `product_quantity`
        MODIFY `Quantity_ID` int(100) NOT NULL AUTO_INCREMENT, 
        AUTO_INCREMENT=34;

          ALTER TABLE `product_quantity`
          ADD CONSTRAINT `product_quantity_ibfk_1` FOREIGN KEY    
          (`Product_ID`) REFERENCES `product_table` (`Product_ID`) 
          ON DELETE CASCADE ON UPDATE CASCADE,
          ADD CONSTRAINT `product_quantity_ibfk_2` FOREIGN KEY (`Size_ID`) 
          REFERENCES `product_size` (`Size_ID`) ON DELETE CASCADE ON
          UPDATE CASCADE;

table product_quantity：

procedure Execute(sCmd: string; sOut : TStringList);
var Process : JProcess;
    Runtime : JRuntime;

    Input   : JInputStream;

    x, bufflen: Integer;

    s: string;
    buff : TJavaArray<Byte>;

begin
  Process := TJRuntime.JavaClass.getRuntime.exec(StringToJString(sCmd));
  Process.waitFor;

  Input := Process.getInputStream;
  bufflen := Input.available;

  buff := TJavaArray<Byte>.Create(bufflen);
  Input.read(buff);

  s := '';

  for x := 0 to bufflen - 1 do
    s := s + chr(buff[x]);

  sOut.Add(s); 

end;

Answer 1

我认为你不需要group_concat。正常group by应该这样做。

SELECT product_table.product_name,
       Sum(product_quantity.quantity),
       CONCAT(' box/es ',
              product_size.size_name, 
              ' size') AS 'SIZE' 
FROM   product_quantity 
RIGHT JOIN product_table 
        ON product_quantity.product_id = product_table.product_id 
LEFT JOIN  product_size 
       ON  product_quantity.size_id = product_size.size_id 
GROUP  BY  product_table.product_name ASC,
           product_size.size_name

提供源数据和更精确的数据输出，我可以创建一个示例演示。

如何在GROUP_CONCAT（）中获取SUM（）

1 个答案: