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xml parsing when unique identifier could be NULL

Posted By:      Posted Date: April 10, 2011    Points: 0   Category :

I am trying to work with the following xml instance where FileIdentifier element allows NULL. However, when parsing it later it generates string conversation related error.

declare @xml XML = '
<CreateUpdateDownloadMessage xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
 <Title xsi:nil="true" />
 <Description xsi:nil="

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