Trigger MSSQL - Output to File (XML) - sql-server

Question

we have a very old ERP system which is badly supported.
Now the warehouse want´s to buy a new "store system" for our goods. It´s a fully automatic store system which need´s data from our ERP system. The support of your ERP system can´t help us, so we have to build a solution of our own.
The idea was to "move" the items for the new storage system to a special storage place called (SHUT1) and output the "part number" and "quantity" to a file (xml) which can be read by the new software.
We can´t change anything in the software of our ERP system, so we have to do it on the SQL Server itself.
(I know, a trigger is not the "best" thing to do, but I have have no other choice)
CREATE TRIGGER tr_LagerShut ON dbo.Lagerverwaltung
AFTER INSERT
AS
BEGIN
IF (SELECT [Lagerort] from Inserted) = 'SHUT1'
BEGIN
DECLARE #Cmd VARCHAR(2000) ;
DECLARE #FormatDate4File VARCHAR(200);
SET #FormatDate4File = (SELECT(SYSUTCDATETIME()));
SET #FormatDate4File = (SELECT REPLACE(#FormatDate4File,' ','-'));
SET #FormatDate4File = (SELECT REPLACE(#FormatDate4File,':','-'));
SET #FormatDate4File = (SELECT REPLACE(#FormatDate4File,'.','-'));
SET #Cmd = ( SELECT [Artikelnummer],[Menge] FROM inserted FOR XML PATH('')) ;
SET #Cmd = 'Echo "' + #Cmd + '" >>"C:\Temp\' + #FormatDate4File +'.xml"' ;
EXEC xp_cmdshell #Cmd ;
END;
END;
The trigger "installs" fine, but if I change a storage place to a new one, the ERP system stalls with "ERROR" (there is no error description :(
If I drop the trigger the system is just running fine again. So I think there is a error in the trigger, but I can´t find it.
Can anybody help please?
Aleks.

Answer 1

Don't know what ERP system stalls with "ERROR" looks like... Frozend GUI? Timeout? Just no file created?
My magic glass bulb tells me the following: You are inserting more than one row at once. If so, this statement will break, because a comparison like this is only valid against a scalar value. If there is more than one row in inserted, this will not work:
IF (SELECT [Lagerort] from Inserted) = 'SHUT1'.
Your trigger can be simplified, but I doubt, that you will like the result. Check this with special characters (like üöä) and check for enclosing "-characters...
CREATE TRIGGER tr_LagerShut ON dbo.Lagerverwaltung
AFTER INSERT
AS
BEGIN
IF EXISTS(SELECT 1 FROM inserted WHERE [Lagerort]='SHUT1')
BEGIN
DECLARE #FileName VARCHAR(255) =REPLACE(REPLACE(REPLACE(SYSUTCDATETIME(),' ','-'),':','-'),'.','-');
DECLARE #Content XML=
(
SELECT [Artikelnummer],[Menge] FROM inserted WHERE [Lagerort]='SHUT1' FOR XML AUTO,ELEMENTS
);
DECLARE #Cmd VARCHAR(4000) = 'Echo "' + CAST(#Content AS VARCHAR(MAX)) + '" >>"c:\temp\' + #FileName + '.xml"' ;
PRINT #cmd;
EXEC xp_cmdshell #Cmd ;
END
END;
This might better be done with BCP.
UPDATE Your comment...
First you should check, if this works at all:
DECLARE #FileName VARCHAR(255) =REPLACE(REPLACE(REPLACE(SYSUTCDATETIME(),' ','-'),':','-'),'.','-');
DECLARE #Content XML=
(
SELECT TOP 5 * FROM sys.objects FOR XML AUTO,ELEMENTS
);
DECLARE #Cmd VARCHAR(4000) = 'Echo "' + CAST(#Content AS VARCHAR(MAX)) + '" >>"c:\temp\' + #FileName + '.xml"' ;
PRINT #cmd;
EXEC xp_cmdshell #Cmd ;
If you find no file in c:\temp\: Are you aware, that SQL-Server will always write in its own context? Might be, that you are awaiting a file in your local c-drive, but the file is written to the Server's machine acutally.
If this works isolatedly, it should work within a trigger too. You might pack the call into BEGIN TRY ... END TRY and add an appropriate CATCH block.

Answer 2

So okay, the "simple" trigger could be really a problem. Now I have this idea:
(one more info: time stamp is not inserted into table "Lagerverwaltung" when a new row is inserted)
Pseudo Code on:
Trigger on Table "Lagerverwaltung"
Check if the storage place(s) is "SHUT1"
If "yes"
DECLARE #FileName VARCHAR(255) =REPLACE(REPLACE(REPLACE(SYSUTCDATETIME(),' ','-'),':','-'),'.','-');
create a new table with name dbo + '.' + #filename
Insert all the data (inserted) + row(SYSUTCDATETIME()) AS TimeStamp where 'Lagerort' = 'SHUT1' into new table named 'dbo.' + #filename
DECLARE #Cmd varchar(4000) = 'bcp "select [Artikelnummer],[Menge],[TimeStamp] FROM [wwsbautest].[dbo].#filename WHERE [Lagerort]=''SHUT1'' AND [Menge] > ''0'' FOR XML AUTO, ELEMENTS" queryout "C:\temp\' + #FileName + '.xml" -c -T';
EXEC xp_cmdshell #Cmd;
Drop table dbo.#filename;
Could somthing like that work?