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!
Eliminate Redundant Data
In the "Database Relation" above, the primary key is made up of the D-ID and the Emp-ID. The database-name relies only on the D-ID. The similar database-name will appear redundantly every time its associated D-ID appears in the Database Relation. The database relation has redundancy, for example D-ID value 4 is oracle is repetitive twice. In addition, it also experiences insertion anomaly that is we cannot enter Sybase in the relation as no employee has that skill.
The deletion anomaly also exists. For instance, if we remove employee with Emp-ID 3; no employee with FoxPro knowledge lefts and the information that D-ID 3 is the code of FoxPro will be gone.
To avoid these troubles, we require second normal form. To achieve this, we isolate the attributes depending on both parts of the key from those depending only on the D- ID. This result in two relations: "Database" which gives the name for every D-ID,
and "Emp-database" which lists the databases for each employee. The employee relation is already in 2NF as all the EMP-ID determines all different attributes
Employee Relation
Emp-ID
Emp-Name
1
Gurpreet Malhotra
2
Faisal Khan
3
Manisha Kukreja
4
Sameer Singh
Emp-database
Relation
D-ID
Database Relation
Database
Access
DB2
FoxPro
Oracle
Describe DROP TABLE command of SQL along with both the options - CASCADE and RESTRICT. DROP TABLE command - This command drops the specified table. Dropping a table also dro
Advantages And Drawbacks Of Ddbms There are various reasons for building distributed database systems, with sharing of data, reliability and availability, and speedup of query
What is a database? Database - Basically in simple terms A database is a collection of inter related data and/or information stored so which it is available to several users
Using Literal Character String Example: To print IS A as one string with column name employee SELECT ENAME || ' IS A ' || JOB AS "EMPLOYEE" FROM EMP;
Wait-die" scheme : The idea is based on non-preventive method. It is based on a simple rule: If Ti requests a database resource that is held by T
What is Cross Product? Simply Cross product is Binary Operator
Insulation between conceptual and physical structures It can be defined as: 1. The Database Administrator should be capable to vary the storage structures without affectin
Explain the two constraints, check and foreign key in SQL along with an example for each. Give the syntax. CHECK constraint - CHECK constraint specifies an expression which
What are the advantages of creating a table from existing table?
What is the way a particular application views the data from the database that the application uses? Sub schema is the way a particular application views the data from the data
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