About: http://webisa.webdatacommons.org/343798244

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Because the entity being passed in is a Customer not a comment and the customer already exists in the database you are not actually calling em.persist but rather em.merge.
http://www.w3.org/ns/prov#wasQuotedFrom	spring.io