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!
Explain the conventions for displaying an ER schema as an ER diagram?
An E-R Diagram scheme might describe certain constraints to that the contents of a database must conform.
Mapping Cardinalities: Express the number of entities to that another entity can be related through a relationship. For binary relationship sets among entity sets A and B, the mapping cardinality must be one of:
1. One-to-one: An entity in A is related along with at most one entity in B, and an entity in B is related with at most one entity in A. 2. One-to-many: An entity in A is related along with any number in B. An entity in B is related with at most one entity in A. 3. Many-to-one: An entity in A is related with at most one entity in B. An entity in B is associated with any number in A. 4. Many-to-many: Entities in A and B are related along with any number from each other.
The suitable mapping cardinality for a particular relationship set depends on the real world being modeled. Cardinality ratios for binary relationships are represented on ER diagram through displaying 1,M, N etc. on the diamonds.
Existence Dependencies: if the existence of entity X depends on the existence of entity Y, then X is said to be existence dependent on Y.
construct an er diagram for a hospital with a set of patients and a set of medical doctors. associate with each patient a log of various test and examination conducted.convert er d
What's the difference between a primary key and a unique key? Both primary key and unique key enforces uniqueness of the column on which they are explained. But by default prim
Desirable Properties Of Decomposition Decomposition is a process of dividing a relation into its projections that will not be disjoint. Please remind the Relational projection
how map binary relation one to one
.#question. Discuss the problem which may arise during concurrency control and recovery in distributed database which are not encountered in controlized database environment.
What do you understand by transitive dependencies? Define with an example any two problems that can take place in the database if transitive dependencies are available in the datab
give some example real life situation where DBMS are most suitable
Consider the following relational schema: Doctor(DName,Reg_no) Patient(Pname, Disease) Assigned_To (Pname,Dname) Give expression in both Tuple calculus and Domain calculus for
Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pictori
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