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CRowset::MoveToRatio

 

The latest version of this topic can be found at CRowset::MoveToRatio.

Fetches rows starting from a fractional position in the rowset.

Syntax

  
      HRESULT MoveToRatio(   
   DBCOUNTITEM nNumerator,   
   DBCOUNTITEM nDenominator,   
   bool bForward = true    
) throw( );  

Parameters

nNumerator
[in] The numerator used to determine the fractional positional from which to fetch data.

nDenominator
[in] The denominator used to determine the fractional positional from which to fetch data.

bForward
[in] Indicates whether to move forward or backward. The default is forward.

Return Value

A standard HRESULT.

Remarks

MoveToRatio fetches rows according roughly to the following formula:

( nNumerator * RowsetSize ) / nDenominator

where RowsetSize is the size of the rowset, measured in rows. The accuracy of this formula depends on the specific provider. For details, see IRowsetScroll::GetRowsAtRatio.

This method requires the optional interface IRowsetScroll, which might not be supported on all providers; if this is the case, the method returns E_NOINTERFACE. You must also set DBPROP_IRowsetScroll to VARIANT_TRUE before calling Open on the table or command containing the rowset.

Requirements

Header: atldbcli.h

See Also

CRowset Class