Update operations in dbms - insert operation, Database Management System

Assignment Help:

Update Operations and Dealing with Constraint Violations

There are three basic operations to be executes on relations:

  • Insertion
  • Deletion
  • Update

The INSERT Operation:

The insert operation permits us to insert a new tuple in a relation. When we try to insert a new record, then any of the following four types of constraints can be violated:

 

  • Key constraint: If the value of the key attribute in new tuple t is the similar as in the existing tuple in relation R.
  • Domain constraint: If the value given to an attribute lies outside the domain of that attribute.
  • Referential Integrity constraint: If the value of the foreign key in t refers to a tuple that doesn't show in the referenced relation.

 • Entity Integrity constraint: If the primary key attribute value of new tuple t is given as null.


Related Discussions:- Update operations in dbms - insert operation

Find out employee who draws salary more than average , Normal 0 ...

Normal 0 false false false EN-US X-NONE X-NONE

Managing databases, Code an Oracle Database trigger to enforce the constrai...

Code an Oracle Database trigger to enforce the constraint that an employee can never change his or her department.

Explain controlled redundancy, Explain controlled redundancy? Controll...

Explain controlled redundancy? Controlled redundancy : The replication of data within the data warehouse for the purposes of improved data access or understand ability.

What is called query processing, What is called query processing? Query...

What is called query processing? Query processing refers to the range of activities included in extracting data from a database.

Which is another name for weak entity, Which is another name for weak entit...

Which is another name for weak entity? Child is another name of weak entity.

Control as a state machine engine, Control as a State Machine Engine F...

Control as a State Machine Engine First let us define the state machine: "the state machine is a machine which is an object but not an application object. It is a part of lang

Explain er model, Question 1 Explain ER model Question 2 What are the...

Question 1 Explain ER model Question 2 What are the characteristics of a computer provided information? Question 3 What are facts and guidelines to be considered when se

What is a view, What is a view? A view is a logical view on one or more...

What is a view? A view is a logical view on one or more tables.  A view on one or more tables i.e., the data from a view is not actually physically kept instead being derived f

Give expression in both tuple calculus and domain calculus, Consider the fo...

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

What are metrics for choosing the best algorithm, What are metrics for choo...

What are metrics for choosing the best algorithm? Matrices for choosing the best algorithms are as below: Computational complexity Ease of understand ability and im

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd