What is secondary index, Database Management System

Assignment Help:

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 memory (Hard Disk). Theoretically, a table may have millions of records (as the telephone directory of a large city), for which even a sparse index becomes so large in size that we cannot keep it in the primary memory. And if we cannot keep the index in the primary memory, then we lose the benefit of the speed of access. For very large table, it is better to classify the index in multiple levels.

 


Related Discussions:- What is secondary index

Column constraints, Column Constraints: NOT NULL, UNIQUE, CHECK, PRIMARY K...

Column Constraints: NOT NULL, UNIQUE, CHECK, PRIMARY KEY, DEFAULT, REFERENCES, On  delete  Cascade :  Using  this  key  whenever  a  parent  row  is  removed  in  a referenced

What is called as an n-way merge, What is called as an N-way merge? The...

What is called as an N-way merge? The merge operation is a generalization of the two-way merge used by the standard in-memory sort-merge algorithm. It merges N runs, so it is k

Functional dependencies and normalization for relational dat, Consider the ...

Consider the 1ollowin8 relation: CAR SALE (Car_id, Option_type, Option_listprice, Sale_date, Option_discountedprice) This relation refers to options installed in cars (e.g., crui

What is boyce-code normal form, Boyce-Code Normal Form (BCNF) A relatio...

Boyce-Code Normal Form (BCNF) A relationship is said to be in BCNF if it is already in 3NF and the left hand side of each dependency is a candidate key. A relation who is in 3N

Large Project, Can you help me with the following: Drop statements for all...

Can you help me with the following: Drop statements for all objects in the lab project. Create statements for all objects of the lab project Create indexes for foreign keys Cre

State the process of inheritance adjustment, Inheritance Adjustment As...

Inheritance Adjustment As in object oriented analysis and design terms inheritance defines a relationship between classes, where as one class shares structure or behaviour def

Define the categories of sql statements, Define the categories of SQL State...

Define the categories of SQL Statements? 1) Statements that don't return a result set. This statement class includes INSERT, DELETE, and UPDATE. 2)Statements that return

Compute natural join and outer join, For the relations R and S given below:...

For the relations R and S given below: R                      S A B C 1 4 7 2 5 8 3 6 9

Prove that a relation which is 4nf must be bcnf, Prove that a relation whic...

Prove that a relation which is 4NF must be BCNF.   Ans Let R be in 4NF.  Suppose it is not in BCNF.  Hence, there exists an FD X→Y in R such that x is not a super key. Although

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