About: http://webisa.webdatacommons.org/361007719

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 in a table that prevents certain types of inconsistent data values from being placed in the column(s).
http://www.w3.org/ns/prov#wasQuotedFrom	sqlwithmanoj.com