Editing Perfect hash function (section)

===Dynamic perfect hashing===
{{main article|Dynamic perfect hashing}}
Using a perfect hash function is best in situations where there is a frequently queried large set, {{mvar|S}}, which is seldom updated. This is because any modification of the set {{mvar|S}} may cause the hash function to no longer be perfect for the modified set. Solutions which update the hash function any time the set is modified are known as [[dynamic perfect hashing]],<ref name="DynamicPerfectHashing">{{citation
 | last1 = Dietzfelbinger | first1 = Martin
 | last2 = Karlin | first2 = Anna | author2-link = Anna Karlin
 | last3 = Mehlhorn | first3 = Kurt | author3-link = Kurt Mehlhorn
 | last4 = Meyer auf der Heide | first4 = Friedhelm
 | last5 = Rohnert | first5 = Hans
 | last6 = Tarjan | first6 = Robert E. | author6-link = Robert Tarjan
 | doi = 10.1137/S0097539791194094
 | issue = 4
 | journal = [[SIAM Journal on Computing]]
 | mr = 1283572
 | pages = 738–761
 | title = Dynamic perfect hashing: upper and lower bounds
 | volume = 23
 | year = 1994}}.</ref> but these methods are relatively complicated to implement.