Hi Shruthi,
1. First get the current context node
lr_property TYPE REF TO if_bol_bo_property_access
lr_property ?= me->typed_context-><context_node_name>->collection_wrapper->get_first().
2. Now fetch data using get_property_as_string() method into variable
lv_partner_no = lr_property->get_property_as_string( '<delivery location>').
3. Featch data from database table by specifying where condition partner_no = lv_partner_no into lv_ext_locno
lv_ext_locno = Database table result (EXT_LOCNO)
4. Assign collected data from database table to context node attributes
lr_valuenode TYPE REF TO CL_BSP_WD_VALUE_NODE.
lr_valuenode ?= me->typed_context-><context_node_name>->collection_wrapper->get_first().
lr_valuenode->SET_PROPERTY_AS_STRING(EXPORTING iv_attr_name = '<delivery location>'
iv_value = lv_ext_locno ).