Query will not update SQL Server - sql-server

Question

In the below code, my second query will not insert into the SQL database, but the first one will update. I can copy the query (from the msgbox i added for testing) and paste it in SQL Server Management Studio, and it will execute fine. I also do not get any error messages back from SQL, though i'm not sure if that code is correct (it was copied + pasted from another source). Also, can i simplify the code to pass both queries at the same time?
Dim Conn As New System.Data.SqlClient.SqlConnection 'sql server datastream connection
Dim Cmd As New System.Data.SqlClient.SqlCommand 'sql command vars
Dim SqlQuery As String 'string var used to hold various SQL queries
Dim data As System.Data.SqlClient.SqlDataReader 'datareader object variable
Dim MVDataset As New DataSet
Dim MVDatatable As DataTable
Dim MVDatarow As DataRow
Private Sub MVUpdateButton_Click(sender As Object, e As EventArgs) Handles MVUpdateButton.Click
vbyn = MsgBox("Are you sure you want to update Tally Sheet Master Variables?" & vbCrLf & vbCrLf & "Changes to these variables will change the functionality of the Tally Sheet!", vbYesNo, )
Try
Select Case vbyn
Case vbNo
GoTo MVTableUpdateBypass
Case vbYes
'get new data from textboxes
Vers = TextBox1.Text
If TextBox2.Text = True Then
Testing = 1
Else
Testing = 0
End If
FlatFeeCharge = TextBox3.Text
PrepricingCharge = TextBox4.Text
SendMailAcct = TextBox5.Text
SendMailPW = TextBox6.Text
TestingEmail = TextBox7.Text
PrePricingEmail = TextBox8.Text
ImperataEmail = TextBox9.Text
'update existing active row to mark inactive
SqlQuery = "Update MasterVars set Active = 0 where PKEY = " & PKEY & ";"
MsgBox(SqlQuery)
If Conn.State = ConnectionState.Closed Then
Conn.ConnectionString = "Data Source=SQL01;Initial Catalog=TallySheet;Integrated Security=SSPI;"
End If
Conn.Open()
Dim MVDataAdapter As New SqlDataAdapter(SqlQuery, Conn)
Dim MVUpdateCommand As SqlCommand
MVUpdateCommand = New SqlCommand(SqlQuery)
MVDataAdapter.UpdateCommand = MVUpdateCommand
'insert new active row
SqlQuery = "Insert into MasterVars (Vers, Testing, FlatFeeCharge, PrePricingCharge, SendMailAcct, SendMailPW, TestingEmail, PrePricingEmail, ImperataEmail, DTS, UserName, Active) Values (" & "'" & Vers & "', " & Testing & ", '" & FlatFeeCharge & "'" & ", '" & PrepricingCharge & "'" & ", '" & SendMailAcct & "'" & ", '" & SendMailPW & "'" & ", '" & TestingEmail & "'" & ", '" & PrePricingEmail & "'" & ", '" & ImperataEmail & "'" & ", '" & Date.Now & "'," & "'QGDOMAIN\" & Environment.UserName & "'," & 1 & ");"
MsgBox(SqlQuery)
Dim MVInsertCommand As SqlCommand
MVInsertCommand = New SqlCommand(SqlQuery)
MVDataAdapter.InsertCommand = MVInsertCommand
MVDataAdapter.Fill(MVDataset, "MasterVars")
End Select
Catch ex As SqlException
Dim i As Integer
Dim errormessages As String
errormessages = ""
For i = 0 To ex.Errors.Count - 1
errormessages = errormessages & " " & ("Index #" & i.ToString() & ControlChars.NewLine _
& "Message: " & ex.Errors(i).Message & ControlChars.NewLine _
& "LineNumber: " & ex.Errors(i).LineNumber & ControlChars.NewLine _
& "Source: " & ex.Errors(i).Source & ControlChars.NewLine _
& "Procedure: " & ex.Errors(i).Procedure & ControlChars.NewLine)
Next i
Console.WriteLine(errorMessages.ToString())
End Try
'reload form with updated variables
Conn.Close()
Conn.Dispose()
MVTableUpdateBypass:
End Sub

Answer 1

The Fill method of the SqlDataAdapter executes the SelectCommand not the UpdateCommand or the InsertCommand. In any case these two commands (and the DeleteCommand) are executed when you call the Update method of the adapter.
Moreover the Update method runs the commands looking for rows changed/added/deleted in the DataTable/DataSet retrieved by the SelectCommand and works only for those rows.
But you don't need an SqlDataAdapter to execute your two queries. You should simply construct an SqlCommand with both texts separated by a semicolon and call ExecuteNonQuery
SqlQuery = "Update MasterVars set Active = 0 where PKEY = #key;" & _
"Insert into MasterVars (Vers, Testing, .....) VALUES (#p1, #o2, ....)"
Using Conn = New SqlConnection("Data Source=SQL01;......")
Using cmd = New SqlCommand(SqlQuery, Conn)
Conn.Open()
cmd.Parameters.Add("#key", SqlDbType.Int).Value = PKEY
cmd.Parameters.Add("#p1", SqlDbType.NVarChar).Value = vers
cmd.Parameters.Add("#p2", SqlDbType.Int).Value = testing
... and so on with other parameters ....
cmd.ExecuteNonQuery()
End Using
End Using
In this incomplete example (too many parameters to write down) I have concatenated the two sql texts in a single string and prepared it with parameter placeholders. Then I build the parameter collection with the exact datatypes required by your table and finally call ExecuteNonQuery to run everything on the database side.
Notice that is not needed to keep global objects like the connection or the command. It is always better to create a local variable, use and destroy it when done. In particular disposable objects like the connection and the command should always created in a Using block