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110 lines
2.8 KiB
110 lines
2.8 KiB
//+---------------------------------------------------------------------------
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//
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// Microsoft Windows
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// Copyright (C) Microsoft Corporation, 1995.
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//
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// File: RowCache.cxx
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//
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// Contents: Forward-only cache
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//
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// Classes: CMiniRowCache
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//
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// History: 05-Jun-95 KyleP Created
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// 14-JAN-97 KrishnaN Undefined CI_INETSRV and related changes
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//
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//----------------------------------------------------------------------------
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#include <pch.cxx>
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#pragma hdrstop
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#include "rowcache.hxx"
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//+---------------------------------------------------------------------------
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//
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// Member: CMiniRowCache::CMiniRowCache, public
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//
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// Synopsis: Initialize
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//
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// Arguments: [Index] -- Identifier. Not used internally.
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// [pRowset] -- Rowset used to fill cache.
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// [cBindings] -- Size of [pBindings].
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// [pBindings] -- Default binding.
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// [cbMaxLen] -- Max length of data fetched via [pBindings]
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//
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// History: 05-Jun-95 KyleP Created.
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//
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//----------------------------------------------------------------------------
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CMiniRowCache::CMiniRowCache( int Index,
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IRowset * pRowset,
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unsigned cBindings,
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DBBINDING * pBindings,
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unsigned cbMaxLen )
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: PMiniRowCache( Index, pRowset, cBindings, pBindings, cbMaxLen )
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{
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Next();
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END_CONSTRUCTION( CMiniRowCache );
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}
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//+---------------------------------------------------------------------------
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//
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// Member: CMiniPositionableCache::Next, public
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//
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// Synopsis: Moves to next row
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//
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// Returns: Move status
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//
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// History: 05-Jun-95 KyleP Created.
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//
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//----------------------------------------------------------------------------
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PMiniRowCache::ENext CMiniRowCache::Next( int iDir /* = 1 */ )
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{
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// Cna only go forward here
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Win4Assert( iDir > 0 );
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//
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// If we had a row in cache, Just advance to it. Otherwise
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// fetch more rows from table.
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//
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_ihrow++;
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if ( _ihrow >= _chrow )
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{
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//
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// Fetch more rows from table.
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//
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HROW * phrow = _ahrow.GetPointer();
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SCODE sc = _pRowset->GetNextRows( 0, 0, _ahrow.Count() , &_chrow, &phrow );
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vqDebugOut(( DEB_ITRACE, "Fetched %d from %d\n", _chrow, _Index ));
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if ( FAILED(sc) )
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{
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vqDebugOut(( DEB_ERROR, "CMiniRowCache: Error 0x%x from GetNextRows\n", sc ));
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_chrow = 0;
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THROW( CException( sc ) );
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}
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else if ( 0 == _chrow && sc != DB_S_ENDOFROWSET )
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{
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return( CMiniRowCache::NotNow );
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}
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_ihrow = 0;
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}
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if( IsAtEnd() )
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{
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return CMiniRowCache::EndOfRows;
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}
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LoadData();
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return CMiniRowCache::Ok;
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}
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