CREATE TABLE [dbo].[ATUserProperty] (
    [UserName]      NVARCHAR (255) NOT NULL,
    [PropertyName]  NVARCHAR (255) NOT NULL,
    [PropertyValue] NVARCHAR (255) NOT NULL,
    CONSTRAINT [PK_ATUserProperty] PRIMARY KEY CLUSTERED ([UserName] ASC, [PropertyName] ASC, [PropertyValue] ASC),
    CONSTRAINT [UQ_ATUserProperty_UserName_PropertyName] UNIQUE ([UserName], [PropertyName]),
    CONSTRAINT [FK_ATUserProperty_ATUser] FOREIGN KEY ([UserName]) REFERENCES [dbo].[ATUser] ([UserName])
);

GO
CREATE NONCLUSTERED INDEX [ATUserProperty_IX_UserName]
    ON [dbo].[ATUserProperty]([UserName] ASC);