FIX: AV with SQLOLEDB Provider When PRINT Statement in Stored Procedure Returns More Than 512 Bytes of Data

With the SQLOLEDB provider that ships with MDAC version 2.5 or 2.5 SP1, calling a Microsoft SQL Server stored procedure with one or more PRINT statements that return more than 512 bytes of data each may result in an access violation. The error message may be as follows:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

This problem was corrected in MDAC 2.6.

Steps to Reproduce Behavior

1. Create the following stored procedure with a PRINT statement returning 700 bytes of data in the SQL Server Northwind database:

   CREATE PROCEDURE sp_Test2
   AS
   set nocount on
   declare @HTMLoutputx varchar(1000)
   select @HTMLoutputx = ''
   
   WHILE LEN(@HTMLoutputx) <= 700 
   BEGIN
   	select @HTMLoutputx = @HTMLoutputx + 'TOO MUCH TEXT IS BAD!'
   END
   
   PRINT @HTMLoutputx
   					

2. Create a Microsoft Visual Basic standard EXE project and set the project reference to Microsoft ActiveX Data Objects 2.5 Library.
3. Add the following function and call it in Form.Load:

   Function Test()
   
   On Error GoTo MAIN_ERROR
   
   Dim adocnn As ADODB.Connection
   Dim adocmd As ADODB.Command
   Dim adorst As ADODB.Recordset
      
   Set adocnn = New ADODB.Connection
   adocnn.CursorLocation = adUseClient
   adocnn.Open "Provider=SQLOLEDB;Data Source=vcdb;Database=northwind;uid=sa;pwd=;"
     
   Set adocmd = New Command
   With adocmd
       .CommandText = "sp_Test2"
       .CommandType = adCmdStoredProc
       .ActiveConnection = adocnn
   End With
   
   ' Execute the command.
   adocmd.Execute , , adExecuteNoRecords
   
   Set adocmd = Nothing
       
   adocnn.Close
   Set adocnn = Nothing
   
   Exit Function
   
   MAIN_ERROR:
      MsgBox Err & " - " & Error$, vbCritical, "CLASS:ReportCriteria,METHOD:LoadLists"
      Exit Function
   
   End Function
   					

4. Run the code and you will see an access violation error returned.