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Unique Constraint in Visual Studio SQL Designer

I was looking at ways to make a newly added column a Unique but not primary column. I had a look at this W3School link . But Instead of following their approach I simply changed my table in the Visual Studio designer as.

CREATE TABLE [dbo].[Userpro] (
    [Id]                INT             NOT NULL IDENTITY,
    [Name]              NVARCHAR (50)   NULL,
    [Postcode]          NVARCHAR (4)    NULL,
    [Gender]            INT             NULL,
    [Blog]              NVARCHAR (MAX)  NULL,
    [FeedBack]          NVARCHAR (MAX)  NULL,
    [Username]          NVARCHAR (50)   NOT NULL Unique,
PRIMARY KEY CLUSTERED ([Id] ASC)
);

Notice that I simply added "Unique" [Username] NVARCHAR (50) NOT NULL Unique . I am unsure if this has the same effect or should I go back and just use the script in the link.

That is perfect.

Adding UNIQUE will have the effect you describe. It is also explained in the link you provide.

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