Differentiate between static hashing and dynamic hashing, Database Management System

Assignment Help:

Differentiate between static hashing and dynamic hashing. 

Ans: Static Hashing comprises the number of primary pages in the directory fixed. So, while a bucket is full, we require an overflow bucket to store any extra records that hash to the full bucket. This can be completed with a link to an overflow page, or a linked list of overflow pages. The linked list can be separate for every bucket, or similar for all buckets that overflow. While searching for a record, the original bucket is accessed first, after that the overflow buckets. Specified there are several keys that hash to the same bucket, locating a record may need accessing multiple pages on disk that greatly degrades performance. 

The dilemma of lengthy searching of overflow buckets is solved by Dynamic Hashing. In Dynamic Hashing the size of the directory grows along with the number of collisions to accommodate new records and prevent long overflow page chains. Extendible and Linear Hashing are two dynamic hashing methods.


Related Discussions:- Differentiate between static hashing and dynamic hashing

What is horizontal fragmentation, What is horizontal fragmentation? Hor...

What is horizontal fragmentation? Horizontal fragmentation divides the relation by assuming every tuple of r to one or more fragments

Database incident table, The Incident table, with an auto-incrementing in...

The Incident table, with an auto-incrementing incident number, etc, looks like: incident_num reporter date time incide

The average amount of their orders , Make SQL statements for the following ...

Make SQL statements for the following scenarios. Your response should contain SQL statement, output and any other assumptions you have made to arrive at the answer. For Colorado cu

Define the two phase locking protocol, Define the Two Phase Locking Protoco...

Define the Two Phase Locking Protocol This is a protocol that is used to make sure serializability of transactions. This protocol needs that every transaction issue lock and u

Parallelism of transaction execution-data fragmentation, Parallelism of tra...

Parallelism of transaction execution: A transaction can be divided into various sub-queries that can operate on fragments in parallel. This enhances the degree of concurrency in t

What is advantage of two-way association, What is advantage of two-way asso...

What is advantage of two-way association? Two-way association advantages are following: a) Independent of the classes. b) Useful for existing predefined classes that are

How to control as concurrent tasks, Control as Concurrent Tasks The ex...

Control as Concurrent Tasks The expression control as simultaneous task means applying control for those events of object which can happen simultaneously. An object can be imp

Define one-way associations using pointers, One-way Associations If an...

One-way Associations If an association is only traversed in single direction, then it is known as one-way association. It is implemented as a pointer or an attribute which con

List any two disadvantages of a database system, List any two disadvantages...

List any two disadvantages of a database system ? The disadvantages of database system are: • Database systems are difficult, complex, and time-consuming to design. • Substanti

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd