core/sql/refresh/RuSimpleRefreshSQLComposer.cpp

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/* -*-C++-*-
******************************************************************************
*
* File:         RuSQLSimpleRefreshComposer.cpp
* Description:  Implementation of class RuSQLSimpleRefreshComposer
*				
*
* Created:      08/13/2000
* Language:     C++
* 
*
* 
******************************************************************************
*/

#include "RuSimpleRefreshSQLComposer.h"
#include "RuTbl.h"

//--------------------------------------------------------------------------//
//	Constructor
//--------------------------------------------------------------------------//

CRUSimpleRefreshSQLComposer::
CRUSimpleRefreshSQLComposer(CRURefreshTask *pTask) 
	: CRURefreshSQLComposer(pTask) 
{}

//--------------------------------------------------------------------------//
//	CRUSimpleRefreshSQLComposer::ComposeRefresh() 
//--------------------------------------------------------------------------//

void CRUSimpleRefreshSQLComposer::ComposeRefresh()
{
	StartInternalRefresh();

	AddDeltaDefListClause();
	
	if (GetRefreshTask().GetMVList().GetCount() > 1)
	{
		AddPipeLineClause();
	}
}

//--------------------------------------------------------------------------//
//	CRUSimpleRefreshSQLComposer::ComposeRecompute() 
//--------------------------------------------------------------------------//

void CRUSimpleRefreshSQLComposer::ComposeRecompute(NoDeleteClause flag)
{
	StartInternalRefresh();

	if (REC_DELETE == flag)
	{
		sql_ += " RECOMPUTE ";
	}
	else
	{
		sql_ += " RECOMPUTE NODELETE ";
	}
}

//--------------------------------------------------------------------------//
//	CRUSimpleRefreshSQLComposer::ComposeLockMV()
// 
//  This function construct an sql statement that locks the MV
//--------------------------------------------------------------------------//

void CRUSimpleRefreshSQLComposer::ComposeLock(const CDSString& name, 
											  BOOL exclusive)
{
	sql_ = "LOCK TABLE " + name;

	if (TRUE == exclusive)
	{
		sql_ += " IN EXCLUSIVE MODE ";
	}
	else
	{
		sql_ += " IN SHARE MODE ";
	}
}

//--------------------------------------------------------------------------//
//	CRUSimpleRefreshSQLComposer::ComposeUnLockMV()
// 
//  This function construct an sql statement that locks the MV
//--------------------------------------------------------------------------//

void CRUSimpleRefreshSQLComposer::ComposeUnLock(const CDSString& name)
{
	sql_ = "UNLOCK TABLE " + name;
}

//--------------------------------------------------------------------------//
//	CRUSimpleRefreshSQLComposer::AddDeltaDefListClause()
//
//	Generate the delta-def clauses syntax for each non-empty T-delta 
//	observed by the MV.
//
//--------------------------------------------------------------------------//

void CRUSimpleRefreshSQLComposer::AddDeltaDefListClause()
{
	RUASSERT(GetRefreshTask().GetDeltaDefList().GetCount() > 0);

	sql_ += "\n FROM ";
	sql_ += (TRUE == GetRefreshTask().IsSingleDeltaRefresh()) ? 
		"SINGLEDELTA " : "MULTIDELTA ";

	DSListPosition pos = GetRefreshTask().GetDeltaDefList().GetHeadPosition();

	for (;;)
	{
		CRUDeltaDef *pDdef = GetRefreshTask().GetDeltaDefList().GetNext(pos);

		CDSString fromEpoch(TInt32ToStr(pDdef->fromEpoch_)) ;
		CDSString toEpoch(TInt32ToStr(pDdef->toEpoch_));

		AddDeltaDefClause(pDdef,fromEpoch,toEpoch);

		if (NULL == pos)
		{
			break;	// The last clause
		}
		else
		{
			sql_ += ", ";
		}
	}	
	if (FALSE == GetRefreshTask().IsSingleDeltaRefresh())
	{
		AddPhaseParam();
	}
}