The column data type in this case is uniqueidentifier. You have a choice to let SQL Server to generate new GUID for it using default newid() when column is not in the INSERT list or you can supply value generated elsewhere.

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>Does the rowguid now get created by SQL Server on an insert as opposed to me creating it when I create records? I would assume so since the default value now says newid()
>Tim
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>>It doesn't do anything besides indicating that the uniqueidentifier values in the column uniquely identify rows in the table. The uniqueness must be enforced through other mechanisms, such as the PRIMARY KEY or UNIQUE KEY constraints for the column.
>>It's primarily used by SQL Server replication. In SQL 2008 it's also required by the new FILESTREAM feature.
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