Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Consider the relations City (city_name, state) Hotel (name, address) City_hotel (hotel_name, city_name, owner) Answer the following queries in relational algebra (i) Find
Define tuple variable? Tuple variables are used for comparing two tuples in the same relation. The tuple variables are explained in the from clause by way of the as clause.
The natural join is equal to which product? The natural join is equal to Combination of projection and Cartesian product
what are information system hirarchy?
Question: This question refers to the database schema. a) Express the following queries in SQL: (i) Write the SQL code that will create the table Company. Your answer sh
Change the city of First Bank Corporation to ‘New Delhi' UPDATE COMPANY SET CITY = ‘New Delhi' WHERE COMPANY_NAME = ‘First Bank Corporation';
imagery
State as Location within a Program In this traditional approach, location of control inside a program totally defines the program state. Any finite state machine may be implem
Define cardinality and participation constraints on a relationship type, completeness constraint on generalization. Ans: Cardinality defines the number of entities to wh
i need help for assignment ..
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd