SQL create xml of Parameters dynamically - sql

Question

Is there a way to query the parameters passed into a stored procedure and return them as XML without creating a string of the parameters and then casting that as xml? I'm looking for something generic, that will work for most SPs without having to physicially code it each time?
I have a bunch of stored procedures that access and modify verify specific information. At the end of the SPs I want to insert into a logging table the name of the SP, and the parameters (in xml) that were used to invoke the SP. I know how to get the name of the SP, and I know how to get a list of the parameters for the SP. What I want is a way to mash it all into XML along the actual values of the parameters that were passed.
I'm looking for something that does this, without the manual coding of each parameter:
DECLARE #L_Data varchar(1500)
SET #L_Data = '<parms>' +
CASE WHEN #ParamRegStationID IS NULL THEN ''
ELSE ',#ParamRegStationID=''' + Convert(varchar, #ParamRegStationID) + '''' END +
CASE WHEN #ParamScheduleID IS NULL THEN ''
ELSE ',#ParamScheduleID=''' + Convert(varchar, #ParamScheduleID) + '''' END +
CASE WHEN #ParamPatientID IS NULL THEN ''
ELSE ',#ParamPatientID=''' + Convert(varchar, #ParamPatientID) + '''' END +
CASE WHEN #ParamHISPatientID IS NULL THEN ''
ELSE ',#ParamHISPatientID=''' + #ParamHISPatientID + '''' END +
CASE WHEN #ParamEvent IS NULL THEN ''
ELSE ',#ParamEvent=''' + #ParamEvent + '''' END +
'</parms>'
This doesn't work, and it isn't as elegant as what I'm hoping for. However, here is an example illustrating what I'm trying to ultimately get to. It creates the temp table, but doesn't add the parameters to it as columns, so I can later extract it as XML.
ALTER PROC uspTest
#ParamID as bigint=null,
#ParamXYZ as varchar(255)=null
as
-- PROC Does whatever it is going to do ....
DECLARE #ProcName varchar(128), #ParmName varchar(128), #ParmType varchar(128), #ParmLen int,
#ParmSQL varchar(1000)
select #ProcName=OBJECT_NAME(##PROCID)
--select * from INFORMATION_SCHEMA.ROUTINES where ROUTINE_TYPE='PROCEDURE' and ROUTINE_NAME=#ProcName
DECLARE csrParms CURSOR
FOR
select PARAMETER_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH from INFORMATION_SCHEMA.PARAMETERS where SPECIFIC_NAME=#ProcName and PARAMETER_MODE='IN'
ORDER BY ORDINAL_POSITION
FOR READ ONLY
OPEN csrParms
FETCH NEXT FROM csrParms
INTO #ParmName, #ParmType, #ParmLen
CREATE TABLE #Parms(ID int identity(1,1), Created DateTime)
INSERT INTO #Parms select GETDATE()
WHILE ##FETCH_STATUS = 0
BEGIN
-- GET Parm value and format as xml attribute to save parm
SET #ParmSQL = 'ALTER TABLE #Parms add ' + #ParmName + ' varchar(' + CAST(ISNULL(#ParmLen, 128) as varchar(128)) + ') NULL '
print #ParmSQL
EXEC (#ParmSQL)
SET #ParmSQL = 'UPDATE #Parms SET ' + #ParmName + ' = ''????'''
print #ParmSQL
--EXEC (#ParmSQL)
FETCH NEXT FROM csrParms
INTO #ParmName, #ParmType, #ParmLen
END
SET #ParmSQL = CAST((select * from #Parms FOR XML RAW) as varchar(1000))
select #ParmSQL
CLOSE csrParms
DEALLOCATE csrParms
This is close to what I'm looking for, I need to know how to replace the ??? with the current value of the parameter dynamically though.
ALTER PROC uspTest
#ParamID as bigint=null,
#ParamXYZ as varchar(255)=null
as
-- PROC Does whatever it is going to do ....
DECLARE #ProcName varchar(128), #ParmName varchar(128), #ParmType varchar(128), #ParmLen int,
#ParmSQL varchar(1000)
select #ProcName=OBJECT_NAME(##PROCID)
--select * from INFORMATION_SCHEMA.ROUTINES where ROUTINE_TYPE='PROCEDURE' and ROUTINE_NAME=#ProcName
set #ParmSQL =
' CREATE TABLE #Parms(ID int identity(1,1), Created DateTime, ' +
STUFF((select (', ' + REPLACE(PARAMETER_NAME,'#','') + ' varchar(' + CAST(ISNULL(CHARACTER_MAXIMUM_LENGTH, 128) as varchar(128)) + ') NULL ')
from INFORMATION_SCHEMA.PARAMETERS where SPECIFIC_NAME='uspTest' and PARAMETER_MODE='IN'
order by ORDINAL_POSITION for XML path(''), type).value('.', 'varchar(max)'), 1, 2, '')
+ ');
' + 'INSERT INTO #Parms (Created) select GETDATE(); ' + STUFF((select (';
UPDATE #Parms SET ' + REPLACE(PARAMETER_NAME,'#','') + ' = ''???''')
from INFORMATION_SCHEMA.PARAMETERS where SPECIFIC_NAME='uspTest' and PARAMETER_MODE='IN'
order by ORDINAL_POSITION for XML path(''), type).value('.', 'varchar(max)'), 1, 2, '')
+ ';
select CAST((select * from #Parms FOR XML RAW) as varchar(1000));'
print #ParmSQL
EXEC (#ParmSQL)
When I execute the proc as:
EXEC uspTest 1, 'test'
Returns:
<row ID="1" Created="2012-04-20T09:44:43.700" ParamID="???" ParamXYZ="???"/>
Prints out:
CREATE TABLE #Parms(ID int identity(1,1), Created DateTime, ParamID varchar(128) NULL , ParamXYZ varchar(255) NULL );
INSERT INTO #Parms (Created) select GETDATE();
UPDATE #Parms SET ParamID = '???';
UPDATE #Parms SET ParamXYZ = '???';
select CAST((select * from #Parms FOR XML RAW) as varchar(1000));

Answer 1

Is this SQL Server 2000 or later? If so you could use the FOR XML clause:
DECLARE #p1 varchar(100) = 'blah'
, #p2 int = 1
, #p3 datetime2(7) = '2011-01-01 13:41'
;
SELECT #p1 StringParm
, #p2 IntParm
, #p3 DateParm
FOR XML RAW
returns:
<row StringParm="blah" IntParm="1" DateParm="2011-01-01T13:41:00"/>
Edit
Ah, the problem there is that you need to parse out the parameter list as well as the values (which are local) into dynamic SQL (where they'd be out of scope).
I suppose you could use INFORMATION_SCHEMA.PARAMETERS to dynamically list the parameters and dbcc_inputbuffers to get the actual values passed. Something like:
create procedure junk
( #int INT
, #string VARCHAR(20)
, #date DATE
)
AS
BEGIN
DECLARE #tmp TABLE
( EventType NVARCHAR(30)
, PARMS INT
, Info NVARCHAR(2000)
);
DECLARE #object NVARCHAR(200);
INSERT INTO #tmp
EXEC('DBCC INPUTBUFFER(##SPID) WITH NO_INFOMSGS');
SELECT INFO
, 'Call' lType
FROM #tmp
UNION
SELECT STUFF(
( SELECT ', ' + parameter_name
FROM INFORMATION_SCHEMA.PARAMETERS
WHERE SPECIFIC_NAME = OBJECT_NAME(##procid)
ORDER BY ORDINAL_POSITION
FOR XML PATH('')
)
, 1
, 2
, ''
)
, 'Parms';
END
That now makes it so that:
exec dbo.junk #int = 3, #string = 'hoo', #date = '2/2/2002';
Returns:
exec dbo.junk #int = 3, #string = 'hoo', #date = '2/2/2002'; Call
#int, #string, #date Parms
Which should get you a ways along. The tricky bit is that DBCC_INPUTBUFFERS returns the EXACT call string. So you'd need to write code to parse out the call to match the input line to the parameter list. If you go that route, you'll likely want a stored function that does the parsing. It would likely take the call string and parameter list something like the return values above, match them, and use the FOR XML clause to return the format you want.
You could also parse call string in a cursor tied to the parameter list. Then you'd pull the parameters in order and look for the commas and #'s. You could still have trouble with parameter values that included those characters if you didn't take that into account.
IMHO, getting that squared away seems like a lot of work compared to a simple select which can almost be copied/pasted from the function header. Of course, if you're talking about a large volume of procedures then it might be worth it. Either way, good luck and thanks for a thought-provoking question.