将两个现有列中的值添加到新列中以获得总计

Question

我们的数据库中有两个名为“ClientIncome”和“PartnerIncome”的现有列。我们想添加一个名为“HouseholdIncome”的新列

我们想将“ClientIncome”和“PartnerIncome”中的值添加到新的“HouseholdIncome”列中？

这是我们数据库的一个小例子。

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Incomes](
    [Id] [int] IDENTITY(1,1) NOT NULL,
    [ClientIncome] [float] NOT NULL,
    [PartnerIncome] [float] NULL,
    [HouseholdIncome] [float] NULL
) ON [PRIMARY]

GO
SET IDENTITY_INSERT [dbo].[Incomes] ON 

GO
INSERT [dbo].[Incomes] ([Id], [ClientIncome], [PartnerIncome], [HouseholdIncome]) VALUES (1, 130.77, NULL, NULL)
GO
INSERT [dbo].[Incomes] ([Id], [ClientIncome], [PartnerIncome], [HouseholdIncome]) VALUES (2, 294.82, 339.28, NULL)
GO
INSERT [dbo].[Incomes] ([Id], [ClientIncome], [PartnerIncome], [HouseholdIncome]) VALUES (3, 0, NULL, NULL)
GO
INSERT [dbo].[Incomes] ([Id], [ClientIncome], [PartnerIncome], [HouseholdIncome]) VALUES (4, 0, 396.82, NULL)
GO
SET IDENTITY_INSERT [dbo].[Incomes] OFF
GO

我们要更新的表有大约 500 万行，因此对于添加此新列的任何帮助将不胜感激。

Answer 1

只需更改您的 table create 语句以使用计算列。

CREATE TABLE [dbo].[Incomes](
    [Id] [int] IDENTITY(1,1) NOT NULL,
    [ClientIncome] [float] NOT NULL,
    [PartnerIncome] [float] NULL,
    [HouseholdIncome] AS COALESCE(ClientIncome, 0.) + COALESCE(PartnerIncome, 0.)
)

如果您的表已经创建，您可以添加一个计算列：

ALTER TABLE dbo.Incomes ADD HouseholdIncome 
    AS COALESCE(ClientIncome, 0.) + COALESCE(PartnerIncome, 0.);