How do I pull a value from column with XML data - sql-server

Question

Hello I have a table called KNXRUNHISTORY and I am trying to pull data from a column called RUNSUMMARYTXT.
The data stored in this column is in xml format.
I am trying to pull the values for these two fields
(entry key="Link1.#OutputType#) and
(entry key="Link6.#SourceRecordsProcessed#)
Any help would be appreciated as I have banging my head against the wall on this one.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE properties SYSTEM
http://java.sun.com/dtd/properties.dtd">
<properties>
<comment>Comment</comment>
<entry key="#InterfaceErrorCount#">0</entry>
<entry key="Link3.#LinkElapsedTime#">0:00:21</entry>
<entry key="Link1.#OutputType#">4</entry>
<entry key="Link6.#SourceRecordsProcessed#">148</entry>

Answer 1

The general idea is to use xpath query to xml data. But in your case there are some pitfalls.
1. Your data aren't xml data type. Most probably data type of the column in varchar(max) or nvarchar(max). It would be OK but
2. You have <!DOCTYPE declaration which requires conversion with with style equals to 2. Encoding must be utf-16 (yours is utf-8). So encoding in the xml declaration must be fixed or just removed.
Here is working example.
declare #tbl table (id int, prop nvarchar(max))
insert #tbl(id,prop) values(1,
N'<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
<properties>
<comment>Comment</comment>
<entry key="#InterfaceErrorCount#">0</entry>
<entry key="Link3.#LinkElapsedTime#">0:00:21</entry>
<entry key="Link1.#OutputType#">4</entry>
<entry key="Link6.#SourceRecordsProcessed#">148</entry></properties>')
;with cte as(
select id, convert(xml,
replace( prop,'<?xml version="1.0" encoding="UTF-8"?>',''),--sanitize data
2 --Enable limited internal DTD subset processing
) x --and then convert to xml data type
from #tbl
)
select t.v.value('entry[#key="Link1.#OutputType#"][1]','int') outputtype,
t.v.value('entry[#key="Link6.#SourceRecordsProcessed#"][1]','int') srcrecprocessed
from cte cross apply x.nodes('properties') t(v) -- use xpath query