VB6 ADO Command to SQL Server

Question

I'm getting an inexplicable error with an ADO command in VB6 run against a SQL Server 2005 database.

Here's some code to demonstrate the problem:

Sub ADOCommand()
   Dim Conn As ADODB.Connection
   Dim Rs As ADODB.Recordset
   Dim Cmd As ADODB.Command

   Dim ErrorAlertID As Long
   Dim ErrorTime As Date

   Set Conn = New ADODB.Connection
   Conn.ConnectionString = "Provider=SQLOLEDB.1;Integrated Security=SSPI;Initial Catalog=database;Data Source=server"
   Conn.CursorLocation = adUseClient
   Conn.Open

   Set Rs = New ADODB.Recordset
   Rs.CursorType = adOpenStatic
   Rs.LockType = adLockReadOnly

   Set Cmd = New ADODB.Command
   With Cmd
      .Prepared = False
      .CommandText = "ErrorAlertCollect"
      .CommandType = adCmdStoredProc
      .NamedParameters = True
      .Parameters.Append .CreateParameter("@ErrorAlertID", adInteger, adParamOutput)
      .Parameters.Append .CreateParameter("@CreateTime", adDate, adParamOutput)
      Set .ActiveConnection = Conn
      Rs.Open Cmd

      ErrorAlertID = .Parameters("@ErrorAlertID").Value
      ErrorTime = .Parameters("@CreateTime").Value
   End With
   Debug.Print Rs.State ' Shows 0 - Closed
   Debug.Print Rs.RecordCount ' Of course this fails since the recordset is closed
End Sub

So this code was working not too long ago but now it's failing on the last line with the error:

Run-time error '3704': Operation is not allowed when the object is closed

Why is it closed? I just opened it and the SP returns rows.

I ran a trace and this is what the ADO library is actually submitting to the server:

declare @p1 int
set @p1=1
declare @p2 datetime
set @p2=''2010-04-22 15:31:07:770''
exec ErrorAlertCollect @ErrorAlertID=@p1 output,@CreateTime=@p2 output
select @p1, @p2

Running this as a separate batch from my query editor yields:

Msg 102, Level 15, State 1, Line 4
Incorrect syntax near '2010'.

Of course there's an error. Look at the double single quotes in there. What the heck could be causing that? I tried using adDBDate and adDBTime as data types for the date parameter, and they give the same results.

When I make the parameters adParamInputOutput, then I get this:

declare @p1 int
set @p1=default
declare @p2 datetime
set @p2=default
exec ErrorAlertCollect @ErrorAlertID=@p1 output,@CreateTime=@p2 output
select @p1, @p2

Running that as a separate batch yields:

Msg 156, Level 15, State 1, Line 2
Incorrect syntax near the keyword 'default'.
Msg 156, Level 15, State 1, Line 4
Incorrect syntax near the keyword 'default'.

What the heck? SQL Server doesn't support this kind of syntax. You can only use the DEFAULT keyword in the actual SP execution statement.

I should note that removing the extra single quotes from the above statement makes the SP run fine.

... Oh my. I just figured it out. I guess it's worth posting anyway.

Answer 1

The answer is that the stored procedure needed SET NOCOUNT ON at the top, since ADO stops the moment it gets a "Rows Affected" response back, and the stored procedure has an update statement before the final select.

I have no clue why the trace is showing syntax from ADODB that doesn't run correctly when submitted on its own, but clearly the ADODB library was NOT getting an error with its queries. The whole problem was SET NOCOUNT ON missing.

Answer 2

In addition to what @Emtucifor mentioned, if your sproc contains PRINT statements (even if only left for debugging), ADO will likewise have a cow, producing the same exact error you are seeing.