[font="Verdana"]Instead of merging the duplicates, you need to remove it. You need to do this work around for the other dependent objects as well which are dependent on Customer's table. Just check out on google what are the techniques for removing duplicates.
By the way, what version SQL Server you are working on? If its SQL Server 2000, there is a bit tedious work around as compare to SQL Server 2005.
Let us know on this.
Thanks,
Mahesh
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