Describe domain constraints, Database Management System

Assignment Help:

Describe domain constraints.

Domain constraints contain entity integrity and referential integrity. The domain is a set of values that might be assigned to an attribute. The entity integrity rule states that no part of a primary key cannot be null. Referential integrity states that every foreign key value must match a primary key value or be null.

Related Discussions:- Describe domain constraints

How can we classify the operations on classes, How can we Classify the oper...

How can we Classify the operations on classes This step fundamentally means all three models functional, object and dynamic (studied in last section) must be combined so that

Differance between internal and external schema, Differance between interna...

Differance between internal and external schema? Internal and external schema: Internal Schema • Describes the physical storage structure • Uses a physical data model External

What is predictive modelling, Problem: (a) Data mining is one of the b...

Problem: (a) Data mining is one of the best ways to analyse data and using software techniques, hidden and unexpected patterns and relationships in sets of data can be extrac

Explain saving derived attributes to avoid re-computation, Saving Derived A...

Saving Derived Attributes to Avoid Re-computation As discussed, "redundancy means duplication of exact data". But, if multiple copies of same data are present in the system,

Define data model, Define data model? A data model is a collection of c...

Define data model? A data model is a collection of conceptual tools for explaining data, data relationships, data semantics and consistency constraints.

Explain data dictionary in short, Explain Data Dictionary in short?

Explain Data Dictionary in short?

Computing the closure of a set of functional dependency, What is meant by c...

What is meant by computing the closure of a set of functional dependency? The closure of F denoted by F + is the set of functional dependencies logically implied by F.

Explain the functions of data manager, Explain the functions of data manage...

Explain the functions of data manager? Functions of Data Manager : - Convert operations in user's queries coming directly through query processor or indirectly in an applicatio

Derived horizontal fragmentation, atient(PNumber, Name, NHS_no, Amount_due,...

atient(PNumber, Name, NHS_no, Amount_due, DNO, Doctor, Medical_Treatment), relation of schema Staff(StaffNum, Name, DNO, Task) and relation of schema Dept(DNO, Name, Location, Dire

What was the method in which records are physically stored, What was the me...

What was the method in which records are physically stored in a specified order according to a key field in each record ? A method in which records are physically stored within

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages