OpemXML - Read last node in SQL - sql

Question

I have a XML like this
<Cat>
<Inner>
<PATCat>
<Pat>SUR</Pat>
<EfDa>20170411093000</EfDa>
</PATCat>
<PATCat>
<Pat>MH</Pat>
<EfDa>20170411094100</EfDa>
</PATCat>
<PATCat>
<Pat>NRO</Pat>
<EfDa>20170411095300</EfDa>
</PATCat>
<PATCat>
<Pat>DAY</Pat>
<EfDa>20170411110900</EfDa>
</PATCat>
</Inner>
</Cat>
and I am using the Query to read the nodes Pat and EfDa
SELECT #PATCat_Pat = Pat,
#PATCat_EfDa = EfDa,
FROM OPENXML(#idoc, '/Cat/Inner', 2)
WITH (
FiCl VARCHAR(20) 'PATCat/Pat',
EfDa VARCHAR(20) 'PATCat/EfDa',
)
The result is #PATCat_Pat = SUR and #PATCat_EfDa = 20170411093000, Whereas I want to read the last node which is "DAY" and "20170411110900"
How can I achieve this? any help would be appreciated
Thanks

Answer 1

You should use value() and last() for xml type instead of OPENXML
DECLARE #xml XML = N'<Cat>
<Inner>
<PATCat>
<Pat>SUR</Pat>
<EfDa>20170411093000</EfDa>
</PATCat>
<PATCat>
<Pat>MH</Pat>
<EfDa>20170411094100</EfDa>
</PATCat>
<PATCat>
<Pat>NRO</Pat>
<EfDa>20170411095300</EfDa>
</PATCat>
<PATCat>
<Pat>DAY</Pat>
<EfDa>20170411110900</EfDa>
</PATCat>
</Inner>
</Cat>'
SELECT #xml.value('(Cat/Inner/PATCat[last()]/Pat)[1]', 'varchar(10)') AS PAT,
#xml.value('(Cat/Inner/PATCat[last()]/EfDa)[1]', 'varchar(30)') AS EfDa
Return
PAT EfDa <br/>
DAY 20170411110900

Answer 2

last() can be used with OPENXML as well.
SELECT Pat,
EfDa
FROM OPENXML(#idoc, '/Cat/Inner/PATCat[last()]', 2)
WITH (
Pat VARCHAR(20) 'Pat',
EfDa VARCHAR(20) 'EfDa'
);

Answer 3

FROM OPENXML with the corresponding SPs to prepare and to remove a document is outdated and should not be used any more (rare exceptions exist). Rather use the appropriate methods the XML data type provides.
From a comment I get, that your function gets the handle, so you'll have to stick with this...
In your question you write, that you want to read the last node which is "DAY" and "20170411110900".
What is your criterion? last or the one with <Pat>="DAY" or - if there might be more of the same - the last of all <PATCat>, which has <Pat>="DAY"? Are the elements always in the same order? Is the last <PATCat> always the one with <PAT>="DAY"?
You have got the solution with last() already. It will find the last <PATCat> no matter what's inside:
'/Cat/Inner/PATCat[last()]'
Looking for the one with "DAY" would be this
'/Cat/Inner/PATCat[(PAT/text())[1]="DAY"][1]'
If there might be more with "DAY" you could replace the last [1] with [last()]