core:mode="OVERWRITE"

Input XML

<shp:Shipment xmlns:shp='SCM.SHIPMENT' 
xmlns:core='CORESYSTEM'>
	<lineItems>
		<lineItem lineItemId='1' numberOfPackages='10' 
typeOfPackaging='EP' />
		<lineItem lineItemId='2' numberOfPackages='20' 
typeOfPackaging='GB' />
		<lineItem lineItemId='3' numberOfPackages='30' 
typeOfPackaging='HP' />
	</lineItems>
</shp:Shipment>

A simple shipment object with line items.

Update XML

<shp:Shipment xmlns:shp='SCM.SHIPMENT' 
xmlns:core='CORESYSTEM' xmlns:base='SCM.BASE'>
	<lineItems>
		<lineItem lineItemId='1' numberOfPackages='100' 
core:mode="OVERWRITE" />
		<lineItem lineItemId='1.1' 
numberOfPackages='110' />
		<lineItem lineItemId='2' numberOfPackages='200' />
		<lineItem lineItemId='3' numberOfPackages='300' 
core:mode="OVERWRITE" />
	</lineItems>
</shp:Shipment>

The attribute core:mode="OVERWRITE" of line items "1" and "3§ changes the mode from "APPEND" to "OVERWRITE".

Thus only the number of packages is taken over. The packing type is removed.

XML result

<shp:Shipment xmlns:shp='SCM.SHIPMENT' 
xmlns:core='CORESYSTEM'>
	<lineItems>
		<lineItem lineItemId='1' 
numberOfPackages='100'/>
		<lineItem lineItemId='1.1' 
numberOfPackages='110'/>
		<lineItem lineItemId='2' numberOfPackages='200' 
typeOfPackaging='GB' />
		<lineItem lineItemId='3' numberOfPackages='300' />
	</lineItems>
</shp:Shipment>

As can be seen, the packaging type has been removed from items "1" and "3", as they were not included in the update XML.