Xpath() return xml[]

Hi,
I have been developing in postgresql for a very short time. I am
currently having problems that I believe can be resolved with the right
query structure but as of yet have not been able to figure it out.
I am using xpath(xpathExpression, xml, Array[Array[]]) function form
8.3.7 (This is the version that I am currently implementing)
This function returns an xml[] ... However, the problem is that in the
xml array return I get the valid return values that I am looking for but
I also get empty sets. How can I return only the sets that returned
valid????
Example of output:
Id | xml[]
1 | <Root/>
2 | <Root/>
3 | {}
4 | {}
Etc.....
I want to only return the rows that did not return {}
Any help with this would be appreciated....
Thank you.

Damian Tamayo
General Dynamics C4 Systems

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