Workflow function

Does any one have PL/SQL Function example on how to change the 'Performer Value' based on the

requisition inventory_org.

Function pseudo code logic:

select  max('Y') from PO_REQUISITION_LINES_all where requisition_header_id = :wf_to_pass and destination_organiation_id in ( 47,48,52 )

then PO_REQ_APPROVED ( Performer Value: 'Role for requisition approved notification_2'

else PO_REQ_APPROVED ( Performer Value: 'Role for requisition approved notification'; -- This attribute is already created in the workflow and available in the list of value of performer value.

thanks