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
Define What are the desirable properties of a decomposition Ans: What are the desirable properties of decomposition - dependency preserving. Because Lossless join and dependen
System Design: An Object Oriented Approach Any software systems always try to change and evolve as technology and business rules evolve. The development of information systems
Having clause This clause is used for producing conditions on grouped information. Example: Find maximum salary and department number of those departments where maxim
What is Functional Dependency? A Functional dependency is shown by X Y among two sets of attributes X and Y that are subsets of R specifies a constraint on the possible tuple
This constraint shows that the key attribute value in each tuple must be unique, i.e., no two tuples have the similar value for the key attribute. This is because the value of the
Define query language? A query is a statement requesting the retrieval of information. The portion of DML that includes information retrieval is known as a query language.
While using extract datasets it is required to have a special workarea for interface False. It is not required to have a special workarea for interface
How can you map NULL values to other values while display? IF( ) , IFNULL( ) keywords are used to do so. They are 'LIMIT' is used for the following kinds of problems: 1) Ans
Company XYZ is an advertising company. It has its own website but the search facilities offered are not reliable. The company is willing to invest to acquire new machines and sof
The External or View Level The external or view level is the highest level of abstraction of database. It gives a window on the conceptual view, which permits the user to see
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