Which sorting technique is used to sort databases, Database Management System

Assignment Help:

Which sorting technique is used to sort databases, whose sizes are very big?  Give one such algorithm.  Why do sorting techniques like quicksort, insertion sort, etc.  not applied on very big databases?    

 Ans:  To sort a large database or file, the sort-merge (or k-way merge) algorithm is extensively used. This is one of the external sorting algorithms. External sorting algorithm considers to sorting algorithms that are appropriate for large file of records stored on disk that do not fit completely in main memory, like most database files. The sort-merge algorithm begins by sorting small subfiles --called runs - of the main file and then merges the sorted runs, making larger sorted subfiles which are merged in turn. Such as other database algorithms, it needs buffer space in main memory, in which the actual sorting and merging of the runs is performed. This algorithm contains two phases:

(1) the sorting phase, and

(2) the merging phase.

 The sorting methods like quick sort, insertion sort, etc. are not applied on large databases as these are internal sorting algorithms, which need buffer space in main memory. The space complexities of these algorithms are O (n) and require a large buffer space in major memory to sort the large database. Hence, internal sorting algorithms are not applied on large databases.


Related Discussions:- Which sorting technique is used to sort databases

Define the terms - physical schema and logical schema, Define the terms  1)...

Define the terms  1) physical schema 2) logical schema.  Physical schema:  The physical schema explains the database design at the physical level, which  is  the  lowest  lev

What is the candidate key for a table with columns, For problems 1-4, give ...

For problems 1-4, give all candidate keys for the tables with FDs specified.  Composite candidate keys must be put in parentheses, and candidate keys must be separated with commas

Define the normalisation form, Define in which normalisation form if an att...

Define in which normalisation form if an attribute of a composite key is dependent on an attribute of other composite key. Ans: 3NF A relation is in 3 NF if an attribute of

What is secondary index, What is Secondary Index While making the index...

What is Secondary Index While making the index, generally the index table is kept in the primary memory (RAM) and the main table, because of its size is keeps in the secondary

Database application and creation, Create Relational Database Model (RDM) f...

Create Relational Database Model (RDM) for Sailing bed and breakfast club Table_Name( attribute_1, attribute_2, attribute_3, ? ,attribute_x) Primary Key ( attribute_1, attribute_2)

Dbms, You are managing the following database system: • DBMS: Oracle 11g ...

You are managing the following database system: • DBMS: Oracle 11g • OS: Sun Solaris • System architecture: Web-based application using ASP.Net • Purpose of Server: HR managem

Benefits and drawbacks of heap files, Benefits of heap files 1.   This i...

Benefits of heap files 1.   This is a easy file Organisation method. 2.   Insertion is somehow capable. 3.   Good for bulk-loading data into a table. 4.   Best if file

Illustration of implementation of inheritance, Illustration of implementati...

Illustration of implementation of inheritance Let us take the illustration of implementation of inheritance. Suppose that we are about to implement the Stack class and by now w

A basic model of database access control, A basic model of Database Access ...

A basic model of Database Access Control Models of database access control have grown out of previous work on protection in operating systems. Let us talk about one simple mode

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