nvarchar(128)

When the parameter to a system function is optional, the current database, host computer, server user, or database user is assumed. Built-in functions must always be followed by parentheses.

System functions can be used in the select list, in the WHERE clause, and anywhere an expression is allowed.

The following example creates a table that uses HOST_NAME() in a DEFAULT definition to record the workstation name of computers that insert rows into a table recording orders.

CREATE TABLE Orders
   (OrderID     int        PRIMARY KEY,
    CustomerID  nchar(5)   REFERENCES Customers(CustomerID),
    Workstation nchar(30)  NOT NULL DEFAULT HOST_NAME(),
    OrderDate   datetime   NOT NULL,
    ShipDate    datetime   NULL,
    ShipperID   int        NULL REFERENCES Shippers(ShipperID));
GO

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