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IRowsetUpdateImpl Class

 

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The OLE DB Templates implementation of the IRowsetUpdate interface.

Syntax

template <  
   class T,   
   class Storage,   
   class UpdateArray = CAtlArray<Storage>,   
   class RowClass = CSimpleRow,   
   class MapClass = CAtlMap <RowClass::KeyType, RowClass*>   
>  
class IRowsetUpdateImpl : public IRowsetChangeImpl<  
   T,   
   Storage,   
   IRowsetUpdate,   
   RowClass,   
   MapClass  
>  

Parameters

T
A class derived from IRowsetUpdateImpl.

Storage
The user record.

UpdateArray
An array containing cached data for updating the rowset.

RowClass
The storage unit for the HROW.

MapClass
The storage unit for all row handles held by the provider.

Members

Interface Methods (Used with IRowsetChange)

SetData Sets data values in one or more columns.

Interface Methods (Used with IRowsetUpdate)

GetOriginalData Gets the data most recently transmitted to or obtained from the data source, ignoring pending changes.
GetPendingRows Returns a list of rows with pending changes.
GetRowStatus Returns the status of specified rows.
Undo Undoes any changes to the row since the last fetch or update.
Update Transmits any changes made to the row since the last fetch or update.

Implementation Methods (Callback)

IsUpdateAllowed Used to check for security, integrity, and so on before allowing updates.

Data Members

m_mapCachedData Contains the original data for the deferred operation.

Remarks

You should first read and understand the documentation for IRowsetChange, because everything described there also applies here. You should also read chapter 6 of the OLE``DB``Programmer's``Reference on setting data.

IRowsetUpdateImpl implements the OLE DB IRowsetUpdate interface, which enables consumers to delay the transmission of changes made with IRowsetChange to the data source and undo changes before transmission.

Important

It is strongly recommended that you read the following documentation BEFORE attempting to implement your provider:

  • Creating an Updatable Provider

  • Chapter 6 of the OLE``DB``Programmer's``Reference

  • Also see how the RUpdateRowset class is used in the UpdatePV sample

Requirements

Header: atldb.h

See Also

OLE DB Provider Templates
OLE DB Provider Template Architecture
Creating an Updatable Provider