CREATE TABLE [dbo].[XtraData]
(
	[Id] UNIQUEIDENTIFIER NOT NULL PRIMARY KEY, 
    [ParentId] UNIQUEIDENTIFIER NULL, 
	[ReferenceId] UNIQUEIDENTIFIER NOT NULL, 
    [Field1] NVARCHAR(100) NULL,
	[Field2] NVARCHAR(100) NULL,
	[Field3] NVARCHAR(100) NULL,
	[Field4] NVARCHAR(100) NULL,
	[Field5] NVARCHAR(100) NULL,
	[Field6] NVARCHAR(100) NULL,
	[Field7] NVARCHAR(100) NULL,
	[Field8] NVARCHAR(100) NULL,
	[Field9] NVARCHAR(100) NULL,
	[Field10] NVARCHAR(100) NULL,
	[Field11] NVARCHAR(100) NULL,
	[Field12] NVARCHAR(100) NULL,
	[Field13] NVARCHAR(100) NULL,
	[Field14] NVARCHAR(100) NULL,
	[Field15] NVARCHAR(100) NULL,
	[Field16] NVARCHAR(100) NULL,
	[Field17] NVARCHAR(100) NULL,
	[Field18] NVARCHAR(100) NULL,
	[Field19] NVARCHAR(100) NULL,
	[Field20] NVARCHAR(100) NULL
)

GO

CREATE INDEX [IX_XtraData_RefId] ON [dbo].[XtraData] ([ReferenceId])