OLEDBSimpleProvider::getEstimatedRows

Returns an estimate of the total number of rows in the data set. With an asynchronous provider, callers can use this method with getRowCount to get an estimate of the percentage of data received.

HRESULT getEstimatedRows (
LONG*pcRows);

Parameter

pcRows

[out]
Estimated number of rows in the data set.

Return Codes

S_OK
The method succeeded.

E_FAIL
A provider-specific error occurred.

Notes

• When an estimate of the number of rows cannot be provided, the provider should return a value of -1.
  
  
• Synchronous providers should not block on a call to getEstimatedRows. They should either return a value of -1 to indicate that they cannot provide an estimate, or they should provide the actual row count (the same as would be obtained through getRowCount).
  
  
• Providers should not return the final row count prior to issuing transferComplete.