Re: Stack Overflow on Insert

Dave,

Using the new ATL 7.0 conversion classes has solved my immediate problem
of stack overflow errors, but I think you have discovered another large
hole in my knowledge. I'm using a CCommand object to get an entire table
from a MS Access database. I'm then 'Insert'ing many records into (the end
of ???) the table.

Should I be doing an 'Update' after each record inserted? (or frequent
UpdateAll calls?) Is this happening automatically when I Close my CCommand
(i.e. recordset)? How will performance be affected?

I appreciate your help.

Jeff Nygren



At what point are you updating the table?  Without explicitly calling the
update of the recordset, you load up memory with all the changes until the
UpdateBatch method is executed.  This is particularly a problem if you
open
the recordset using a LockBatch type of parameter.

To resolve this, you could issue the update with each record added, or key
the updatebatch method to execute after a certain number of records have
been added.

Dave Edwinson


-----Original Message-----
From: Jeff Nygren [mailto:[email protected]]
Sent: Friday, May 24, 2002 9:09 AM
To: [email protected]
Subject: Re: Stack Overflow on Insert

...
Thank you for taking a look at this. Here are the 'guts' of my sample app.

Jeff Nygren


   hr = DBOutputCommand.CreateAccessor(nOutputCols, &pszColumnBuf[1],
sizeof(TCHAR)*nOutputCols*256);
   for (ULONG lCol = 1; lCol <= nOutputCols; lCol++)
      DBOutputCommand.AddBindEntry(lCol, DBTYPE_WSTR, 256,
&pszColumnBuf[lCol]);

   CString  sQuery("select * from tablename");
   hr = DBOutputCommand.Open(m_DBOutputSession, sQuery, &PropertySet);

   // Loop through records
   for (nRecordNum = 0; nRecordNum < NUMROWS; nRecordNum++)
   {
      // Loop through columns of output database
      for (int iColumn = 0; iColumn < NUMCOLS; iColumn++)
         wcsncpy((WCHAR*)pszColumnBuf[iColumn + 1],
(WCHAR*)T2OLE(strValue), 128);

      if (S_OK == (hr = DBOutputCommand.Insert()))
      {
        ...


-----Original Message-----
From: Jeff Nygren [mailto:[email protected]]
Sent: 23 05 2002 15:50
To: [email protected]
Subject: [OLEDB_DEV] Stack Overflow on Insert

I have some code that adds records to a MS Access database. If I try to
add too many records, I get a stack overflow. I'm guessing there is
something more I need to do, but I don't know what it is. My code is
basically:

...

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