数据库多行转换为单一列

数据库存储与实际显示需求不一样时，我们得写SQL来实现数据呈现：

如：

 

先来看看数据表：

 

CREATE TABLE [dbo].[Expenses]
(
    [Date] DATE,
    [Description] NVARCHAR(40),
    [Charge] DECIMAL(18,2)
)
GO

Source Code

 

然后，我们为表填充一些数据，比如春节购买开支：

 

INSERT INTO [dbo].[Expenses] ([Date],[Description],[Charge]) VALUES 
("2020-01-22",N"鱿鱼",305.40),
("2020-01-22",N"猪肉",110.60),
("2020-01-22",N"青菜",36.90),
("2020-01-22",N"酒",30.00),
("2020-01-22",N"米",75.00),

("2020-01-23",N"鱿鱼",200.40),
("2020-01-23",N"猪肉",50.00),
("2020-01-23",N"青菜",14.30),
("2020-01-23",N"酒",30.00),
("2020-01-23",N"米",20.00),

("2020-01-24",N"鱿鱼",460.00),
("2020-01-24",N"猪肉",200.00),
("2020-01-24",N"青菜",90.00),
("2020-01-24",N"酒",50.00),
("2020-01-24",N"米",300.00)

GO

Source Code

 

所有数据准备完毕，现在写SQL来实现此功能：

 

SELECT E1.[Date],E1.[Charge] AS N"鱿鱼",E2.[Charge] AS N"猪肉",E3.[Charge] AS N"青菜",E4.[Charge] AS N"酒", E5.[Charge] AS N"米"  FROM
[dbo].[Expenses] AS E1,[dbo].[Expenses] AS E2,[dbo].[Expenses] AS E3,[dbo].[Expenses] AS E4,[dbo].[Expenses] AS E5
WHERE E1.[Date] = E2.[Date] AND E2.[Date] = E3.[Date] AND E3.[Date] = E4.[Date] AND E4.[Date] = E5.[Date]
AND E1.[Description] = N"鱿鱼" AND E2.[Description] = N"猪肉" AND E3.[Description] = N"青菜" AND E4.[Description] = N"酒" AND E5.[Description] = N"米"  
GO

Source Code