About: http://webisa.webdatacommons.org/20404450

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	A constraint is a property assigned to a column or the set of columns
http://www.w3.org/ns/prov#wasQuotedFrom	databasejournal.com