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
*/
	private void mappingParentColumnBinding( ) throws DataException
	{
		IBaseQueryDefinition queryDef =  baseQueryDefn;
		while ( queryDef instanceof ISubqueryDefinition )
		{
			queryDef = queryDef.getParentQuery();
			Map parentBindings = queryDef.getBindings( );
			addParentBindings(parentBindings);
		}
	}
	/**
	 * 
	 * @param parentBindings
	 * @throws DataException 
	 */
	private void addParentBindings( Map parentBindings ) throws DataException {
		Iterator it = parentBindings.keySet( ).iterator( );
		while ( it.hasNext( ) )
		{
			Object o = it.next( );
			IBaseExpression expr = ((IBinding)parentBindings.get( o )).getExpression( );
			if ( expr instanceof IScriptExpression )
			{
				if (!ExpressionUtil.hasAggregation( ( (IScriptExpression) expr ).getText( ) ))
				{
					if ( baseQueryDefn.getBindings( )
							.get( o ) == null )
					{	
						IBinding binding = new Binding( o.toString( ) );