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

Explain cursors in sql, Explain cursors in SQL? Cursors in SQL - An o...

Explain cursors in SQL? Cursors in SQL - An object used to store the output of a query for row-through-row processing through the application programs. Cursors are constructs

Enhanced entity relationship, what do you understand by enhanced entity-rel...

what do you understand by enhanced entity-relationship

What are advantages of object-oriented programming paradigm, What is the ma...

What is the major advantage of object-oriented programming paradigm? The ability to modify the explanation of an object without affecting the rest of the system is the main adv

Having clause-data manipulation language, Having clause This clause...

Having clause This clause is used for producing conditions on grouped information. Example: Find maximum salary and department number of those departments where maxim

Sql, Events4Fun is an event management company in Europe with branches in S...

Events4Fun is an event management company in Europe with branches in South America as well. The company is well-known for its efficiency, good-quality services, and affordable char

Differentiate between a subquery and a join, Differentiate between a subque...

Differentiate between a subquery and a join If we need to acquire information from one or more tables after that either subquery or join can be used. If the columns which are t

Create table employee and enter employee data in sql, Create table employee...

Create table employee and enter employee data in SQL? Consider the following relational schemas: EMPLOYEE (EMPLOYEE_NAME, STREET, CITY) WORKS (EMPLOYEE_NAME, COMPANYNAME, SAL

What is the state machine engine, What is the State Machine Engine The...

What is the State Machine Engine The straightest approach to implement control is to have any way of explicitly representing and executing state machines. With the help of thi

Deadlock and its prevention, Deadlock And Its Prevention: As seen earlier,...

Deadlock And Its Prevention: As seen earlier, though two phase locking protocol handles the trouble of serialisability, but it causes some troubles also. For instance, consider th

Describe specialsation and generalization, Describe Specialsation and gener...

Describe Specialsation and generalization? Specialisation /generalization: This is a top down and bottom up approach to the design of database. It displays the IS_A relation

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