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.
Illustrate the view of software architecture A model is a semantically closed abstraction of system composes of elements. It can be visualized using any of the following five v
what are the topics in data management
What is Oracle databse structure? Oracle database structure: The relational model has three main aspects: Structures: Structures are well-defined objects which store th
Regional Gardens has many nurseries, including Wagga Wagga, Bathurst, Albury, Orange, and Dubbo. Each nursery is known by its campus code, eg WW, B, A, O and D respectively. Additi
Why are cursors necessary in embedded SQL? A cursor is an object used to store the output of a query for row-by-row processing through the application programs. SQL statements
If the deletion violates referential integrity constraint, then three alternatives are available: Default option: - refuse the deletion. It is the job of the DBMS to describ
State The position of object at any moment is called state. An object can have many states depend upon time. After receiving some input instructions, the object can change its
what is database management system? & why it is required?
statical data
Describe the definition of a transaction in SQL Ans: The SQL transaction starts implicitly. Transactions are finished by either Commit work that commits the transaction and st
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