How to do xml parsing in store procedure - sql-server

Question

I have a table which contains xml format request.
For eg:
Api_id xmlRequest Sent_Time
1 ........ 07-04-2016 10:07:12:345
1 ........ 08-04-2016 10:03:12:345
2 ........ 09-04-2016 10:08:12:345
2 ........ 09-04-2016 10:09:12:345
For Api_id, we can have multiple request.
XML request schema is same, but has different values.
Xml request is as :
<?xml version="1.0"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd">
<PARTS>
<TITLE>Computer Parts</TITLE>
<PART>
<ITEM>Motherboard</ITEM>
<MANUFACTURER>ASUS</MANUFACTURER>
<MODEL>P3B-F</MODEL>
<COST> 123.00</COST>
</PART>
</PARTS>
I need store procedure, so I can send API_id, and value(which i can search in xml request ) and get xml requests based on Item value.
CREATE PROCEDURE getxmlRequest(
#Api_Id INT
#value
,#xmlRequest VARCHAR(max) out)
AS
BEGIN
Set #xmlRequest = SELECT xmlRequest FROM Api_request
WHERE Api_id = #Api_id
/* here need to iterate over #xmlRequest */
Set #Xmlvalue = SELECT X.R.value ('.','nvarchar (150)')
FROM #xmlRequest.nodes(XPATH) X(R)
if(#XmlValue = #value)
/*Add to result so i can return
/*I want to return all #xmlRequest if we has value from xpath*/
END;
So my question If
Set #xmlRequest = SELECT xmlRequest FROM Api_request
WHERE Api_id = #Api_id
If we will get multiple result : does it possible to iterate? If yes how efficient i can ?
How to return multiple #xmlRequest as Api_id is same?
Does any one work on such kind of scenario? Please help me.

Answer 1

Try this query
SELECT *,CONVERT(XML,xmlRequest,2)
FROM Api_request
WHERE Api_id = #Api_id
AND CONVERT(XML,xmlRequest,2).value('(/PARTS/PART/ITEM)[1]','nvarchar(max)')
LIKE '%'+#value+'%'
It will return all the xmlRequest where contains your value

Answer 2

Your question is quite unclear, but please have look on this:
CREATE TABLE #testTbl(Api_id INT, xmlRequest VARCHAR(MAX), SentTime DATETIME);
INSERT INTO #testTbl VALUES
(1,'<?xml version="1.0"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd">
<PARTS>
<TITLE>Computer Parts</TITLE>
<PART>
<ITEM>Motherboard</ITEM>
<MANUFACTURER>ASUS</MANUFACTURER>
<MODEL>P3B-F</MODEL>
<COST> 123.00</COST>
</PART>
</PARTS>',GETDATE())
,(1,'<?xml version="1.0"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd">
<PARTS>
<TITLE>Computer Parts</TITLE>
<PART>
<ITEM>CPU</ITEM>
<MANUFACTURER>INTEL</MANUFACTURER>
<MODEL>CPUModelXY</MODEL>
<COST>345.00</COST>
</PART>
</PARTS>',GETDATE())
,(2,'<?xml version="1.0"?>
<!DOCTYPE PARTS SYSTEM "parts.dtd">
<PARTS>
<TITLE>Car Parts</TITLE>
<PART>
<ITEM>Wheel</ITEM>
<MANUFACTURER>Pirelli</MANUFACTURER>
<MODEL>WheelModelXY</MODEL>
<COST>100.00</COST>
</PART>
</PARTS>',GETDATE());
This will rerturn all rows where the Api_id=1
SELECT Api_id
,CONVERT(XML,xmlRequest,2) AS xmlRequest
,SentTime
FROM #testTbl
WHERE Api_id=1;
This will return table-like data. You can use "normal" SQL (WHERE, GROUP BY, ...) to continue
DECLARE #Api_Id INT=NULL;
WITH MyRequests AS
(
SELECT Api_id
,RealXML.value('(/PARTS/TITLE)[1]','varchar(max)') AS Title
,part.value('ITEM[1]','varchar(max)') AS Item
,part.value('MANUFACTURER[1]','varchar(max)') AS Manufacturer
,part.value('MODEL[1]','varchar(max)') AS Model
,part.value('COST[1]','decimal(12,4)') AS Cost
,SentTime
FROM #testTbl
CROSS APPLY(SELECT CONVERT(XML,xmlRequest,2) AS RealXML) AS ConvertedToXML
CROSS APPLY RealXML.nodes('/PARTS/PART') AS A(part)
WHERE #ApiId IS NULL OR Api_Id=#Api_Id
)
SELECT *
FROM MyRequests
--WHERE ...
--GROUP BY ...
--ORDER ...
;
The result
+---+----------------+-------------+---------+--------------+----------+-------------------------+
| 1 | Computer Parts | Motherboard | ASUS | P3B-F | 123.0000 | 2016-04-07 11:54:08.980 |
+---+----------------+-------------+---------+--------------+----------+-------------------------+
| 1 | Computer Parts | CPU | INTEL | CPUModelXY | 345.0000 | 2016-04-07 11:54:08.980 |
+---+----------------+-------------+---------+--------------+----------+-------------------------+
| 2 | Car Parts | Wheel | Pirelli | WheelModelXY | 100.0000 | 2016-04-07 11:54:08.980 |
+---+----------------+-------------+---------+--------------+----------+-------------------------+
Clean Up
GO
DROP TABLE #testTbl;