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!
Describes the several relationship constraints through giving suitable example?
Constraints on relationships: There are two kinds of constraints on relationships.
1) Mapping cardinalities or cardinality ratios express the number of entities to that another entity can be associated through a relationship set. For a binary relationship set among entities A and B. The mapping cardinality may be any one of the subsequent:
a) 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.b) One to Many: An entity in A can be related with any number in B but an entity in B is associated with at most one in A.c) Many to one: An entity in A is related with at most one in B but an entity in B is associated with any number in A.d) Many to Many: An entity in A and B can be associated along with any number of entities in the other entity set.
2) Participation constraints: The participation of an entity set E in a relationship set R is said to be total if every entity in E participates within at least one relationship in R. If only a few entities in E participation of entity set E in relationship R is said to be partial.
In which relational modes, cardinality is termed? Answer : Cardinality is termed in a number of tuples relational modes.
Explain Data Dictionary in short?
Homework chapter 10 no 3
What is a B+-Tree index? A B+-Tree index takes the form of a balanced tree in which each path from the root of the root of the root of the tree to a leaf of the tree is of the
What is a SELECT operation? The select operation selects tuples that please a given predicate. We use the lowercase letter σ to denote selection.
We require an advanced system for a Sports Centre, you are concerned only with representing the data discussed below about bookings and members. (The complete system may contain ot
Relational and E-R Model There are three types of constraints on relational database that have: DOMAIN CONSTRAINT PRIMARY KEY CONSTRAINT INTEGRITY CONSTRAINT
what is attribute is attribute inheritance in dbms?
Consider a database application that deals with an Employee relation with information such as SIN, name, data of birth (DOB), and DID (the ID of the department at which the employe
OBJECTIVES After going through this unit you should be capable to: Explain the File Based system and its limitations; Explain the structure of DBMS; Explain the
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