PRB: DB_E_ERRORSOCCURRED returned from Open when using GROUP BY and Aggregate function (236933)

MORE INFORMATION

Steps to reproduce the behavior

1. Create a table in SQL Server. To do this, follow these steps:
   1. Connect to SQL Server with SQL Query Analyzer.
   2. Switch to the Northwind database.
   3. Paste the following code in SQL Query Analyzer:

      Create table myProducts ( ProductName NVarchar (40),  UnitsOnOrder smallint)
      go
      insert into myProducts values ( 'A', 1)
      go 

   4. Press F5
2. Use the ATL OLE DB Consumer Wizard to create a CCommand class that supports the change, insert and delete operations
   1. Start Visual C++ 6.0
   2. On the File menu, click New. The New dialog box appears.
   3. On the Projects tab, click MFC AppWizard(exe).
   4. On the Projects tab, type Q236933 in the Project box, and then click OK. The MFC AppWizard appears.
   5. Click Dialog based as your application type.
   6. Click Finish, and then click OK.
   7. On the Insert menu, click New ATL Object, and then click OK. The ATL Object Wizard appears.
   8. In the left pane, click Data Access, click the Consumer icon in the right pane, and then click Next. The ATL Object Wizard Properties dialog box appears.
   9. Click Select Datasource. The Create New Datalink dialog box appears.
   10. Click Microsoft OLE DB Provider for SQL Server, and then click Next. Set your SQL SERVER connection to use the Northwind database, and then click OK.
   11. In the Select Database Table dialog box, use the tree control to select the dbo.myProducts table, and then click OK. You return to the ATL Object Wizard Properties dialog box.
   12. Click to select the Change, Insert, and Delete check boxes to support the changing, inserting, and deleting of records in the rowset.
   13. Click OK.
3. Using the new CCommand derived class, do the following:
   1. Open the dbomyProducts.h file in the workspace.
   2. Locate the following code:

      DEFINE_COMMAND(CdbomyProductsAccessor, _T(" \
      	SELECT \
      		ProductName, \
      		UnitsOnOrder  \
      		FROM dbo.myProducts"))
      

   3. Replace it with the following code:

      DEFINE_COMMAND(CdbomyProductsAccessor, _T(" \
      	SELECT \
      		ProductName, \
      		MAX(UnitsOnOrder)  \
      		FROM dbo.myProducts GROUP BY ProductName"))

   4. Open the Q236933Dlg.cpp file in the workspace
   5. Add the following code in the top of windows after the #include "Q236933.h" statement:

      #include "dbomyProducts.h"

   6. Locate the following code:

      BOOL CQ1321321Dlg::OnInitDialog()

   7. Paste the following code above the OnInitDialog() function:

      HRESULT hr;
      CdbomyProducts rs1;
      hr= rs1.Open();
      // 0x80040e21 is the value of DB_E_ERRORSOCCURRED.
      	if (hr==0x80040E21) MessageBox("Command Failed.\rDB_E_ERRORSOCCURRED",NULL,MB_OK);

   8. Press Ctrl+F5 to build and run the application. You receive the following error message:
      Command Failed. DB_E_ERRORSOCCURRED