I am encountering a strange problem when attempting to execute a DELETE query agains a SQL Server table using VB.NET, SQL Command, and Parameters.
I have the following code:
Try
sqlCommand.Transaction = transaction1
sqlCommand.Connection = conn
sqlCommand.CommandText = sqlQuery
sqlCommand.Parameters.Add("@userID", SqlDbType.Int).Value = Convert.ToInt32(userID)
sqlCommand.Parameters.Add("@groupID", SqlDbType.Int).Value = Convert.ToInt32(groupID)
''#Delete the user from the group.
MessageBox.Show("User: " + Convert.ToString(userID) + " Group: " + Convert.ToString(groupID))
MessageBox.Show("Param, UserID: " + sqlCommand.Parameters.Item(0).Value.ToString)
MessageBox.Show("Param, GroupID: " + sqlCommand.Parameters.Item(1).Value.ToString)
return_deleteUser = sqlCommand.ExecuteNonQuery()
Catch ex As Exception
transaction1.Rollback()
Dim hr As Integer = Marshal.GetHRForException(ex)
MsgBox("Removal of user from group has failed: " + ex.Message() & hr)
End Try
Which executes the following SQL Query:
Dim sqlQuery As String = "DELETE FROM MHGROUP.GROUPMEMS WHERE USERNUM =@userID AND GROUPNUM =@groupID"
My problem is that when the code executes, there is no error reported at all. I have ran SQL Profiler and the query doesn't appear in the trace list. The three messageboxes that I have added all return the correct values, and if I was to execute the SQL query against the table with the values the query succeeds. Both the userID and groupID are 3-digit integers.
Can anyone suggest why the code is not working as intended, or any further debugging that I can use to step through the code? Ideally I would love to see the completed SQL query with the parameters completed, but I haven't found out how to do this.
EDIT: I have the following later in the code to check if the execute's all processed successfully:
If return_insertEvent > 0 And return_updateUser > 0 And return_nextSID > 0 And return_deleteUser > 0 Then
MessageBox.Show("Success")
return_removeADGroup = RemoveUserFromGroup(userID, groupName)
MessageBox.Show("Remove FS User from AD Group: " + return_removeADGroup)
transaction1.Commit()
transaction2.Commit()
transaction3.Commit()
transaction4.Commit()
returnResult = 1
Else
transaction1.R开发者_如何学Goollback()
transaction2.Rollback()
transaction3.Rollback()
transaction4.Rollback()
returnResult = 0
End If
If you require any further information please don't hesitate in contacting me.
You are missing a Transaction.Commit
Update in respone to additional info added to question:
Why do you have 4 transactions? Since their commit and rollbacks are all executed together, you only need one transaction. I suggest you use a TransactionScope
You can assign the current transaction to ADO.NET Command objects:
ADO.NET and System.Transactions
Transaction Processing in ADO.NET 2.0
I might guess that your calling proc has the values of userid and groupid backwards. If the DELETE doesn't find a matching record, it will complete successfully, but not do anything. I suggest wrapping your delete up in a stored procedure. Then you can add code to test if the parameter values are getting through correctly.
Create Procedure UserDelete
@userid int, @groupID int
As
BEGIN
Select @userid as UID, @groupID as GID INTO TESTTABLE;
DELETE FROM MHGROUP.GROUPMEMS WHERE USERNUM =@userID AND GROUPNUM =@groupID;
END
Run your code then go check the contents of TESTTABLE.
FWIW: I don't like trying to get the whole parameter declaration in one line. Too much going on for me. I like this...
Dim pUID as New Parameter("@userid", SqlDbType.Int)
pUID.Value = userid
cmd.Parameters.Add(pUID)
After some time debugging and sql tracing, I have found out that the stupid application that the DB belongs to treats the group members differently, the groups reside in a administration database, but the users membership to the group resides in another database.
Thank you to everyone above who provided there time and thoughts in assisting with the code. I have changed the code as recomended to use only two transactions and two connections (1 for the admin and sub-database). The code is much nicer now and is that bit easier to read.
Thanks again,
Matt
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