core/sql/refresh/RuLogCleanupSQLComposer.h

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#ifndef _RU_LOG_CLEANUP_SQL_COMPOSER_H_
#define _RU_LOG_CLEANUP_SQL_COMPOSER_H_

/* -*-C++-*-
******************************************************************************
*
* File:         RuLogCleanupSQLComposer.h
* Description:  Definition of class CRULogCleanupSQLComposer
*				
*
* Created:      09/25/2000
* Language:     C++
* 
*
* 
******************************************************************************
*/

#include "RuSQLComposer.h"
#include "RuLogCleanupTaskExecutor.h"

class CRULogCleanupTask;
class CRUTbl;

//--------------------------------------------------------------------------//
//	CRULogCleanupSQLComposer
//
//	This class composes the syntax of the DELETE statements
//	for deletion from the IUD- and range-log in the log
//	cleanup task.
//
//--------------------------------------------------------------------------//

class REFRESH_LIB_CLASS CRULogCleanupSQLComposer : public CRUSQLComposer {

private:
	typedef CRUSQLComposer inherited;

public:
	CRULogCleanupSQLComposer(CRULogCleanupTask *pTask);
	virtual ~CRULogCleanupSQLComposer() {}

public:
	enum { 
	
		// Epochs 0..+100 in the log are reserved for special purposes
		MAX_SPECIAL_EPOCH = 100,

		// To avoid lock escalation, delete 10000 rows in txn
		MAX_ROW_TO_DELETE_IN_SINGLE_TXN = 10000 
	};

public:
	void ComposeIUDLogCleanup(CRULogCleanupTaskExecutor::SQL_STATEMENT type);
	void ComposeRangeLogCleanup();
        void composeGetRowCount();

private:
        void ComposeHeader(const CDSString &tableName, CRULogCleanupTaskExecutor::SQL_STATEMENT type);
	
private:
	//-- Prevent copying
	CRULogCleanupSQLComposer(const CRULogCleanupSQLComposer &other);
	CRULogCleanupSQLComposer &operator = (const CRULogCleanupSQLComposer &other);

private:
	CRUTbl &tbl_;
	TInt32 maxInapplicableEpoch_;
};

#endif