SQL每日一题-0823(难度提升题)

今日SQL题：库存调拨优化

难度系数：🌟🌟☆☆☆☆☆☆☆☆

1、题目要求

分析每个产品在不同仓库的库存差异，并找出从哪个仓库调拨以满足需求。
查询结果显示：库存充足的源仓库名称、库存不足的目标仓库名称、需要调拨的产品名称、源仓库与目标仓库之间的库存差异数、调拨的总成本(根据调拨的差异数和产品单价计算)

2、表和虚拟数据

sql 复制代码

--仓库信息表
CREATE TABLE IM_Warehouses (
    WarehouseID INT PRIMARY KEY, -- 仓库ID
    WarehouseName NVARCHAR(100), -- 仓库名称
    Location NVARCHAR(100) -- 仓库位置
);
 
--产品表
CREATE TABLE IM_Products (
    ProductID INT PRIMARY KEY, -- 产品ID
    ProductName NVARCHAR(100), -- 产品名称
    Category NVARCHAR(50), -- 产品类别
    UnitCost DECIMAL(10, 2), -- 产品单价
    ReorderLevel INT -- 再订货水平
);
 
--产品库存表
CREATE TABLE IM_Inventory (
    InventoryID INT PRIMARY KEY, -- 库存ID
    WarehouseID INT, -- 仓库ID
    ProductID INT, -- 产品ID
    Quantity INT, -- 库存数量
    LastUpdated DATETIME, -- 最后更新时间
    FOREIGN KEY (WarehouseID) REFERENCES IM_Warehouses(WarehouseID),
    FOREIGN KEY (ProductID) REFERENCES IM_Products(ProductID)
);
 
--订单表
CREATE TABLE IM_Orders (
    OrderID INT PRIMARY KEY, -- 订单ID
    OrderDate DATETIME, -- 订单日期
    CustomerID INT, -- 客户ID，引用IM_Customers表
    WarehouseID INT, -- 仓库ID，引用IM_Warehouses表
    FOREIGN KEY (WarehouseID) REFERENCES IM_Warehouses(WarehouseID)
);
 
--订单明细表
CREATE TABLE IM_OrderDetails (
    OrderDetailID INT PRIMARY KEY, -- 订单详情ID
    OrderID INT, -- 订单ID，引用IM_Orders表
    ProductID INT, -- 产品ID，引用IM_Products表
    Quantity INT, -- 订单数量
    UnitPrice DECIMAL(10, 2), -- 产品单价
    FOREIGN KEY (OrderID) REFERENCES IM_Orders(OrderID),
    FOREIGN KEY (ProductID) REFERENCES IM_Products(ProductID)
);
 
--客户表
CREATE TABLE IM_Customers (
    CustomerID INT PRIMARY KEY, -- 客户ID
    CustomerName NVARCHAR(100), -- 客户名称
    CustomerEmail NVARCHAR(100) -- 客户邮箱
);
 
--模拟数据
INSERT INTO IM_Warehouses (WarehouseID, WarehouseName, Location) VALUES
(1, '京东智能仓储-北京库', '北京'),
(2, '阿里智能仓储-杭州库', '杭州'),
(3, '华为智能仓储-深圳库', '深圳'),
(4, '中兴智能仓储-成都库', '成都'),
(5, '顺丰智能仓储-广州库', '广州');
 
INSERT INTO IM_Products (ProductID, ProductName, Category, UnitCost, ReorderLevel) VALUES
(1, '笔记本电脑', '电子产品', 1200.00, 50),
(2, '智能手机', '电子产品', 800.00, 100),
(3, '办公椅', '家具', 250.00, 30),
(4, '耳机', '配件', 150.00, 70),
(5, '显示器', '电子产品', 300.00, 20),
(6, '键盘', '配件', 80.00, 40),
(7, '鼠标', '配件', 40.00, 50),
(8, '打印机', '电子产品', 150.00, 10),
(9, '台灯', '家具', 90.00, 25),
(10, 'USB闪存', '配件', 20.00, 150);
 
INSERT INTO IM_Customers (CustomerID, CustomerName, CustomerEmail) VALUES
(1, '客户A', 'customerA@example.com'),
(2, '客户B', 'customerB@example.com'),
(3, '客户C', 'customerC@example.com'),
(4, '客户D', 'customerD@example.com'),
(5, '客户E', 'customerE@example.com'),
(6, '客户F', 'customerF@example.com'),
(7, '客户G', 'customerG@example.com'),
(8, '客户H', 'customerH@example.com'),
(9, '客户I', 'customerI@example.com'),
(10, '客户J', 'customerJ@example.com');
 
INSERT INTO IM_Inventory (InventoryID, WarehouseID, ProductID, Quantity, LastUpdated) VALUES
(1, 1, 1, 60, '2024-08-01'),
(2, 1, 2, 120, '2024-08-01'),
(3, 1, 6, 200, '2024-08-01'),
(4, 1, 9, 30, '2024-08-01'),
(5, 2, 1, 80, '2024-08-01'),
(6, 2, 3, 20, '2024-08-01'),
(7, 2, 7, 90, '2024-08-01'),
(8, 2, 10, 150, '2024-08-01'),
(9, 3, 4, 50, '2024-08-01'),
(10, 3, 5, 10, '2024-08-01'),
(11, 3, 8, 5, '2024-08-01'),
(12, 4, 2, 60, '2024-08-01'),
(13, 4, 5, 40, '2024-08-01'),
(14, 4, 6, 120, '2024-08-01'),
(15, 5, 3, 80, '2024-08-01'),
(16, 5, 7, 30, '2024-08-01'),
(17, 5, 8, 20, '2024-08-01');
 
INSERT INTO IM_Orders (OrderID, OrderDate, CustomerID, WarehouseID) VALUES
(1, '2024-08-02', 1, 1),
(2, '2024-08-05', 2, 2),
(3, '2024-08-07', 3, 3),
(4, '2024-08-10', 4, 1),
(5, '2024-08-12', 5, 2),
(6, '2024-08-14', 6, 3),
(7, '2024-08-16', 7, 4),
(8, '2024-08-18', 8, 5),
(9, '2024-08-20', 9, 1),
(10, '2024-08-22', 10, 2);
 
INSERT INTO IM_OrderDetails (OrderDetailID, OrderID, ProductID, Quantity, UnitPrice) VALUES
(1, 1, 1, 10, 1200.00),
(2, 1, 2, 20, 800.00),
(3, 2, 3, 15, 250.00),
(4, 2, 4, 5, 150.00),
(5, 3, 5, 2, 300.00),
(6, 3, 6, 8, 80.00),
(7, 4, 7, 5, 40.00),
(8, 4, 8, 1, 150.00),
(9, 5, 9, 3, 90.00),
(10, 5, 10, 10, 20.00),
(11, 6, 1, 2, 1200.00),
(12, 6, 3, 5, 250.00),
(13, 7, 4, 10, 150.00),
(14, 7, 6, 3, 80.00),
(15, 8, 5, 7, 300.00),
(16, 8, 9, 4, 90.00),
(17, 9, 2, 6, 800.00),
(18, 9, 10, 8, 20.00),
(19, 10, 7, 5, 40.00),
(20, 10, 8, 2, 150.00);

3、预期查询结果

4、解题思路

1)、查找仓库库存差异：比较每个产品在不同仓库的库存差异，选择库存充足的仓库

(源仓库)和库存不足的仓库（目标仓库）

2)、计算库存差异：比较每种产品在不同仓库之间的库存差异

3)、计算总数量差异和总成本：根据计算出的库存差异，统计每种产品的总数量差异、计算

调拨所需总成本