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!
Determine the Strong and Weak Entity
Based on the method of foreign key, there might be arise a situation when we have to relate an entity having a primary key of its own and an entity not having a primary key of its own. In such a case, the entity having its own primary key is known as a strong entity and the entity not having its own primary key is known as a weak entity. Whenever we need to relate a strong and a weak entity together, the ERD would alter just a little.
Say, for instance, we have a statement "A Student lives in a Home." STUDENT is obviously a strong entity having a primary key Roll. But HOME might not have a unique primary key, as its only attribute Address may be shared by a lot of homes (what if it is a housing estate?). HOME is a weak entity in this case.
Define an operator that a Relational Algebra does not have Ans: Relational Algebra does not have Aggregation operators.
What is Candidate Key Super Key or Candidate Key: It is such an attribute of a table that can uniquely recognize a row in a table. Generally they have unique values and can n
Explain the ACID properties of a transaction Ans: ACID properties are a significant concept for databases. The ACID stands for Atomicity, Consistency, Isolation, and Durability
Describe the Composite Key Composite Key: Sometimes one key is not enough to uniquely recognize a row. E.g. in a single class Roll is enough to search a student, but in the w
explain the level architectures of the database management system
Advantages of Observation Methods: Bailey has pointed out four advantages of observation: 1. Superior in Data Collection on Non Verbal Behavior: When a person a opi
We will explain here an example database application having COLLEGE database and use it in showing several E-R modelling concepts. College database remains track of faculty, Stu
Let us now talk about the relational operations: SELECT The select operation is used to select few specific record from the database based on different criteria, This is a un
An important first step to the statistical analysis of data is to "get to know your data". The following tasks should contribute to this. (a) To the right of the dataset cons
What is schema
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd