Bug 195970 Two issues when evaluate a query inlcuding a subquery[07]
Description: Currently, when evaluating a query which includes a subquery, the query will be evaluated twice. The binding of query will pass to subquery twice. If user write a java script such as new Date() and i++. The result of query will be incorrect. Another issue: when write the report document, the binding of query will be written twice and the performance is not good to evalulate it twice.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedQuery.java
switch ( ce.getOperator( ) )
		{
			case IConditionalExpression.OP_TOP_N :
				prefix = "Total.isTopN";
				break;
			case IConditionalExpression.OP_TOP_PERCENT :
				prefix = "Total.isTopNPercent";
				break;
			case IConditionalExpression.OP_BOTTOM_N :
				prefix = "Total.isBottomN";
				break;
			case IConditionalExpression.OP_BOTTOM_PERCENT :
				prefix = "Total.isBottomNPercent";
				break;
		}
		
		if( prefix != null )
		{
			ce = new ConditionalExpression( prefix+"("
					+ ce.getExpression( ).getText( ) + ","
					+ ce.getOperand1( ).getText( ) + ")",
					IConditionalExpression.OP_TRUE );
		}
		return ce;
	}
	
	/**
	 * Return the QueryResults. But the execution of query would be deferred
	 *