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!
Differentiate between logical database design and physical database design. Show how this separation leads to data independence?
Basis
Logical Database Design
Physical Database Design
Task
Maps or transforms the conceptual schema (or an ER schema) from the high-stages data model into a relational database schema.
The specifications for the stored database within terms of physical storage structures, record placement, and indexes are designed.
Choice of criteria
The mapping can proceed in two levels:
1. System independent mapping but data model-depending.
2. tailoring the schemas to a specific DBMS.
The following criteria are frequent used to guide the choice of physical database design option:
1. Response Time option
2. Space Utilization
3.Transaction throughout
Result
DDL statements within the language of the chosen DBMS that specify the conceptual and external stages schemas of the database system. But if the DDL statements involve a few physical design parameters, a completed DDL specification must wait until after the physical database.
An initial determination of storage structures and the access paths for the database files. This corresponds to defining the internal schema in terms of Data Storage Definition Language.
The database design is separated into various phases. The logical database design and physical database design are two of them. This separation is commonly based on the concept of three-level architecture of DBMS that gives the data independence. Therefore, we can say in which this separation leads to data independence since the output of the logical database design is the conceptual and external level schemas of the database system that is independent from the output of the physical database design which is internal schema.
What is inheritance? Inheritance is an object orientation concept that allows reusability of code / design. Basic sense of inheritance is that if one class is predefined than a
Sparse and Dense Indexes These indexes in principle are the similar as that of indexes used at the back of the book. The key facts of the indexes are: They are arranged
What is storage manager? A storage manager is a program module that gives the interface between the Low level data kept in a database and the application programs
what is Storage-Device Hierarchy question
I am using Siteground. And my database is full of limit so need someone who reduces the data which no need. This is very simple and simple task. Skills required are Databa
Question: Describe briefly the three parts of the Relational Model. (a) The term integrity refers to the accuracy or correctness of the data in the database. Define the fol
Explain the Role of a database administrator a. Defining the Schema The DBA describes the schema which consists of the structure of the data in the application. The DBA
What are referential integrity constraints? A value that appears in single relation for a given set of attributes also appears for a particular set of attributes in another rel
What will be create when a primary key if combined with a foreign key? A primary key if combined with a foreign key it creates Parent-Child relationship between the tables that
Question : Mr. Smith Harry has a car manufacturing company which has recently integrated management information system. He wishes to obtain more information on ethics and socia
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