CREATE TABLE dbo.InvoiceHeader
(
InvoiceHeaderID integer NOT NULL
CONSTRAINT PK_InvoiceHeader
PRIMARY KEY CLUSTERED
IDENTITY(1,1),
InvoiceNumber AS RIGHT('00000000' + CONVERT(CHAR(8), InvoiceHeaderID), 8),
InvoiceDate date NOT NULL
CONSTRAINT DF_InvoiceHeader_InvoiceDate
DEFAULT (GETDATE()),
CustomerNumber integer NOT NULL
);
CREATE NONCLUSTERED INDEX IX_dbo_InvoiceHeader__InvoiceNumber
ON dbo.InvoiceHeader (InvoiceNumber);