Bug 213907 Provide a copy constructor for SubqueryDefinition.
Engine need a copy constructor to generate a SubqueryDefinition from an ISubqueryDefinition and change the name of the query.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedQuery.java
} );
		}
	}
	
	/**
	 * Prepares all expressions in the given collection
	 * 
	 * @param expressions
	 * @param groupLevel
	 * @param afterGroup
	 * @param cx
	 * @throws DataException 
	 */
	private void prepareExpressions( Collection expressions, int groupLevel,
			boolean afterGroup, boolean isDetailedRow, Context cx ) throws DataException
	{
	    if ( expressions == null )
	        return;
	    
	    AggregateRegistry reg = this.aggrTable.getAggrRegistry( groupLevel,
	    		-1,
				isDetailedRow,
				cx );
	    Iterator it = expressions.iterator();
	    while ( it.hasNext() )
	    {
	        prepareExpression((IBaseExpression) it.next(), groupLevel, cx, reg);
	    }
	}