如何定义适用于 DataSet 表中的多个列的 UNIQUE 约束？

Question

I have the following table defined in a.sql script file.

---

CREATE TABLE [HwComponent](
    [HwComponentId] [int] NOT NULL,
    [HwComponentTypeId] [int] NOT NULL,
    [ManufactureId] [int] NOT NULL,
    [SerialNumber] [nvarchar](100) NOT NULL,
    [AssignmentType] [nvarchar](1000) NOT NULL,
    [IsFunctional] [nvarchar](10) NOT NULL,
    [Note] [nvarchar](4000) NULL,

    CONSTRAINT [PK_HwComponent] PRIMARY KEY ([HwComponentId]),
    CONSTRAINT (FK1_HwComponent] FOREIGN KEY ([HwComponentTypeId]) REFERENCES [HwComponentType] ([HwComponentTypeId)] ON DELETE NO ACTION ON UPDATE NO ACTION
    CONSTRAINT (FK2_HwComponent] FOREIGN KEY ([HwComponentTypeId], [ManufactureId]) REFERENCES [HwComponentTypeManufacturerInfo] ([HwComponentTypeId], [ManufactureId]) ON DELETE NO ACTION ON UPDATE NO ACTION,
    CONSTRAINT (UI1_HwComponent] UNIQUE ([HwComponentTypeId], [ManufactureId], [SerialNumber]))

GO

---

I now need to define a new table in the DataSet Designer to match.

I believe I have everything defined correctly, except the UNIQUE constraint that requires all 3 columns be considered together as the unique constraint.

How do I define the UNIQUE constraint for this table in the DataSet Designer ?

SQL CE Service 4.0 SP1: VS Prof 2017 - Version 15.8.7

Answer 1

Does this work for you?

CREATE UNIQUE INDEX ixYourConstraint ON HwComponent (col1, col2);

This similar post might be of help to you: MsSql Compact, unique constraint on two and more columns

Answer 2

Your code should work if properly formatted. You have parens where you shouldn't:

CREATE TABLE [HwComponent](
    [HwComponentId] [int] NOT NULL,
    [HwComponentTypeId] [int] NOT NULL,
    [ManufactureId] [int] NOT NULL,
    [SerialNumber] [nvarchar](100) NOT NULL,
    [AssignmentType] [nvarchar](1000) NOT NULL,
    [IsFunctional] [nvarchar](10) NOT NULL,
    [Note] [nvarchar](4000) NULL,

    CONSTRAINT PK_HwComponent PRIMARY KEY ([HwComponentId]),
    CONSTRAINT FK1_HwComponent FOREIGN KEY ([HwComponentTypeId]) REFERENCES [HwComponentType] ([HwComponentTypeId)] ON DELETE NO ACTION ON UPDATE NO ACTION
    CONSTRAINT K2_HwComponent FOREIGN KEY ([HwComponentTypeId], [ManufactureId]) REFERENCES [HwComponentTypeManufacturerInfo] ([HwComponentTypeId], [ManufactureId]) ON DELETE NO ACTION ON UPDATE NO ACTION,
    CONSTRAINT UI1_HwComponent UNIQUE ([HwComponentTypeId], [ManufactureId], [SerialNumber])
);

I would advise you to get rid of all the square braces. They just make the code harder to write and to read and to modify.

Answer 3

Thanks Algef and Gordon for you responses.

Sorry about the confusion. My bad. :-) The SQL sample works fine. I used it as an example only. I actually need to represent this table exactly using the DataSet Designer in VS. The table should look something like the following when done.

HwComponent Table in the DataSet Designer

My problem is I'm not having success in defining the UNIQUE group properly in the DataSet Designer . I need to define a UNIQUE GROUP that consists of the HwComponentTypeId, ManufactureId and SerialNumber columns.

Any ideas?

Thanks again for any help