Bug 208511 The memory cache issue when preview crosstab in deploy environment[1102]
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/impl/DataRequestSessionImpl.java
String[] leafLevelKeyColumn = new String[levels.size( )];
			for ( int k = 0; k < levels.size( ); k++ )
			{
				TabularLevelHandle level = (TabularLevelHandle) levels.get( k );
				List levelKeys = new ArrayList();
				Iterator it = level.attributesIterator( );
				while( it.hasNext( ) )
				{
					LevelAttributeHandle levelAttr = (LevelAttributeHandle)it.next( );
					levelKeys.add( OlapExpressionUtil.getAttributeColumnName( level.getName( ),
							levelAttr.getName( ) ) );
				}
				if ( DesignChoiceConstants.LEVEL_TYPE_DYNAMIC.equals( level.getLevelType( ) )
						&& level.getDisplayColumnName( ) != null )
				{
					levelKeys.add( OlapExpressionUtil.getDisplayColumnName( level.getName( ) ) );
				}
				leafLevelKeyColumn[k] = level.getName( );
				
				levelInHier[k] = CubeElementFactory.createLevelDefinition( level.getName( ),
						new String[]{
							level.getName( )
						},
						this.toStringArray( levelKeys ) );
			}
			
			createLeafLevel( levels, levelInHier, leafLevelKeyColumn );
		
			iHiers.add( cubeMaterializer.createHierarchy( dim.getName( ), hierhandle.getName( ),
					new DataSetIterator( this, hierhandle, appContext ),