EDUCBA

EDUCBA

MENUMENU
  • Free Tutorials
  • Free Courses
  • Certification Courses
  • 360+ Courses All in One Bundle
  • Login

Integrity Constraints in DBMS

By Priya PedamkarPriya Pedamkar

Home » Data Science » Data Science Tutorials » Database Management Tutorial » Integrity Constraints in DBMS

Integrity Constraints in DBMS

Introduction to Integrity Constraints in DBMS

Integrity constraints in Database Management Systems (DBMS) are a set of rules that are applied on the table columns or relationships to ensure that the overall validity, integrity, and consistency (i.e. the quality) of the data present in the database table is maintained. Each and every time a table insert, update, delete, or alter operation is performed, it is evaluated against the terms or rules mentioned in the integrity constraint. The data is inserted, updated, deleted, or altered only if the result of the constraint comes out to be True. Thus, integrity constraint prevents accidental damage to the database by an authorized user.

Types of Integrity Constraints in DBMS

in relational DBMS, we primarily have four types of integrity constraints, namely :

Start Your Free Data Science Course

Hadoop, Data Science, Statistics & others

Types of Integrity Constraints in DBMS

  • Domain Integrity Constraint
  • Entity Integrity Constraint
  • Referential Integrity Constraint
  • Key Constraints

In this particular article, we will try to learn different types of integrity with the help of a few examples.

1. Domain Integrity Constraint

A domain integrity constraint is a set of rules that restricts the kind of attributes or values a column or relation can hold in the database table. For example, we can specify if a particular column can hold null values or not, if the values have to be unique or not, the data type or size of values that can be entered in the column, the default values for the column, etc.

For example, we want to create a “customer_details” table, with information such as customer id, customer name, the number of items purchased, date of purchase, etc. So, in order to ensure domain integrity, we can specify the customer_id has to be unique, the quantity of items purchased has to be an integer number only and the date of purchase has to be a date or timestamp, etc. This can be achieved in the following manner while creating the table.

CREATE TABLE customer_details
(
customer_id character varying(255) NOT NULL,
customer_name character varying(255) NOT NULL,
quantity integer NOT NULL,
date_purchased date
);

Or we can do it using the browser menu as shown in the pictures below.

customer_details

Go to the Browser section -> Select the required database from the Databases -> Select the required schema from the Schemas -> Right-click on the Tables -> Choose Create Table … -> Fill in the details on the dialog box -> In the columns tab mention the domain constraint that you want.

Now let’s try to make an insert query and check if the domain constraints have been successfully applied.

INSERT INTO public.customer_details(
customer_id, customer_name, quantity, date_purchased)
VALUES ('US1002','Kabir Khan','ABC', 2019-12-31);

Integrity Constraints in DBMS2

In the above image, we can see that for the ‘quantity’ attribute when we tried to insert a character value instead of an integer, the domain constraint enables the server to throw an error.

Popular Course in this category
Sale
All in One Data Science Bundle (360+ Courses, 50+ projects)360+ Online Courses | 1500+ Hours | Verifiable Certificates | Lifetime Access
4.7 (3,220 ratings)
Course Price

View Course

Related Courses
SQL Training Program (7 Courses, 8+ Projects)PL SQL Training (4 Courses, 2+ Projects)Oracle Training (14 Courses, 8+ Projects)

2. Entity Integrity Constraint

Entity Integrity Constraint is used to ensure the uniqueness of each record or row in the data table. There are primarily two types of integrity constraints that help us in ensuring the uniqueness of each row, namely, UNIQUE constraint and PRIMARY KEY constraint.

The unique key helps in uniquely identifying a record in the data table. It can be considered somewhat similar to the Primary key as both of them guarantee the uniqueness of a record. But unlike the primary key, a unique key can accept NULL values and it can be used on more than one column of the data table.

CREATE TABLE Students(
Student_ID int NOT NULL,
Student_Name varchar(255) NOT NULL,
Class_Name varchar(255) UNIQUE,
Age int,
PRIMARY KEY (Student_ID)
);

Integrity Constraints in DBMS3

Now let’s try to make an insert query and check if the entity constraints have been successfully applied.

INSERT INTO public.students(
student_id, student_name, class_name, age)
VALUES (32,'ABC','V',12),(32,'XYZ','V',11);

Integrity Constraints in DBMS4

We can see in the above image that when we tried to insert duplicate values, the entity constraints forced the server to throw errors.

3. Referential Integrity Constraint

Referential Integrity Constraint ensures that there always exists a valid relationship between two tables.This makes sure that if a foreign key exists in a table relationship then it should always reference a corresponding value in the second table or it should be null.

We can create relationships between two tables in the following manner. Here, we have created a “Department” table and then “Employees” where the “department” attribute references to Department_ID” in the former table.

CREATE TABLE Department(
Department_ID int NOT NULL,
Department_Name varchar(255) NOT NULL,
PRIMARY KEY(Department_ID)
);
CREATE TABLE Employees(
Employee_ID int NOT NULL,
Employee_Name varchar(255) NOT NULL,
Department int NOT NULL,
Age int,
FOREIGN KEY (Department) REFERENCES Department(Department_ID)
);

After a few insertion operations, the data in the “Department” table looks something like this.

Department table

Now let’s try to make an insert query and check if the entity constraints have been successfully applied.

INSERT INTO public.employees(
employee_id, employee_name, department, age)
VALUES (1002,'K K Davis',10,43);

entity constraints

In the above example, we tried to insert a department that does not exist in the “Department” table, hence it gives an error. 

4. Key Constraints

There are a number of key constraints in SQL that ensure that an entity or record is uniquely or differently identified in the database. There can be more than one key in the table but it can have only one primary key.

Some of the key constraints in SQL are :

  1. Primary Key Constraint
  2. Foreign Key Constraint
  3. Unique Key Constraint

Conclusion

Integrity constraints in DBMS are a set of rules that are required to ensure consistency and integrity of data in the database.

Recommended Articles

This is a guide to Integrity Constraints in DBMS. Here we discuss an introduction to Integrity Constraints in DBMS and top 4 types with detail explanation. You can also go through our other related articles to learn more –

  1. What is RDBMS?
  2. Specialization in DBMS
  3. ER Model in DBMS
  4. Normal Forms in DBMS

All in One Data Science Bundle (360+ Courses, 50+ projects)

360+ Online Courses

1500+ Hours

Verifiable Certificates

Lifetime Access

Learn More

0 Shares
Share
Tweet
Share
Primary Sidebar
Database Management Tutorial
  • DBMS
    • Introduction To DBMS
    • DBMS ER Diagram
    • What is DBMS?
    • DBMS Canonical Cover
    • DBMS Log-Based Recovery
    • DBMS Multivalued Dependency
    • Netezza Database
    • DBMS Concepts
    • DBMS Constraints
    • DBMS_Scheduler
    • B+ Tree in DBMS
    • DBMS_LOB
    • dbms entity
    • DBMS Foreign Key
    • DBMS Users
    • DBMS_Metadata.get_ddl
    • Relational Algebra in DBMS
    • DBMS Components
    • DBMS Features
    • DBMS Models
    • DBMS Relational Model
    • Hashing in DBMS
    • DBMS network model
    • Relationship in DBMS
    • ER Model in DBMS
    • Data Models in DBMS
    • Static Hashing in DBMS
    • Advantages of DBMS
    • dbms_output.put_line
    • DBMS Data Dictionary
    • dbms_xplan.display_cursor
    • Normal Forms in DBMS
    • DBMS helps achieve
    • DBMS 3 tier Architecture
    • Relational Calculus in DBMS
    • Serializability in DBMS
    • File Organization in DBMS
    • DBMS Transaction Processing
    • States of Transaction in DBMS
    • Functional Dependency in DBMS
    • Generalization in DBMS
    • Data Independence in DBMS
    • Lock Based Protocols in DBMS
    • Deadlock in DBMS
    • Integrity Constraints in DBMS
    • Concurrency Control in DBMS
    • Validation Based Protocol in DBMS
    • DBMS Locks
    • Normalization in DBMS
    • Transaction Property in DBMS
    • Specialization in DBMS
    • Aggregation in DBMS
    • Types of DBMS
  • DataBase Management
    • Text Data Mining
    • Roles of Database Management System in Industry
    • SQL Server Database Management Tools
    • Database administrator skills
    • Database Management Systems Advantages
    • Database Testing Interview Questions
    • Data Administrator
    • Database Administrator
    • Database Management Software
    • DataStage
    • Types of Database Models
    • Types of Database
    • Hierarchical Database Model
    • Relational Database
    • Relational Database Advantages
    • Operational Database
    • What is RDBMS?
    • What is DB2?
    • Data Masking Tools
    • Database Security
    • Data Replication
    • Bitmap Indexing
    • Second Normal Form
    • Third Normal Form
    • Fourth Normal Form
    • Data Definition Language
    • Data Manipulation Language
    • Data Control Language
    • Transaction Control Language
    • Conceptual Data Model
    • Entity-Relationship Model
    • Relational Database Model
    • Sequential File Organization
    • Checkpoint in DBMS
    • Teradata Create Table
    • Centralized Database
    • Data Storage in Database
    • Thomas write Rule
    • DBA Interview Questions
    • What is JDBC?
    • jdbc hive
    • Apriori Algorithm
    • JDBC Architecture
    • JDBC Interview Questions
    • Wildcard Characters
    • Distributed Database System
    • Multidimensional Database
  • PL/SQL
    • What is PL/SQL?
    • Careers in PL/SQL
    • PLSQL procedure
    • PL/SQL Exception
    • PL/SQL LIKE
    • PL/SQL Raise Exception
    • PLSQL rowtype
    • PLSQL? bind variables
    • PL/SQL Record
    • PL/SQL WITH
    • PL/SQL bulk collect
    • PL/SQL Block Structure
    • PL/SQL else if
    • PL/SQL nvl2
    • PL/SQL Package
    • PL/SQL exists
    • PL/SQL instr
    • PL/SQL listagg
    • PL/ SQL Formatter
    • PLSQLlength
    • PL/SQL Commands
    • PL/SQL Data Types
    • CASE statement in PL/SQL
    • PL/SQL IF Statement
    • Loops in PL/SQL
    • PL/SQL Add Column
    • For Loop in PLSQL
    • PL/SQL Cursor Loop
    • PLSQL Array
    • Cursors in PL/SQL
    • PL/SQL FOR Loop Cursor
    • PL/SQL Queries
    • PL/SQL SELECT INTO
    • PL/SQL TO_CHAR
    • PL/SQL UNION
    • PL/SQL NOT EQUAL
    • PL/SQL varray
    • PL/SQL Concatenate
    • PL/SQL UPDATE
    • PL/SQL TRIM
    • PL/SQL GROUP BY
    • PL/SQL GOTO
    • PL/SQL Date Functions
    • PL/ SQL having
    • PL/SQL to_DATE
    • PL/SQL NVL
    • PLSQL format date
    • PLSQL mod
    • PLSQL round
    • PL/SQL Boolean
    • PL/SQL exit
    • PL/SQL DECODE
    • PL/SQL ROWNUM
    • PLSQL?pivot
    • PLSQL string functions
    • PL/SQL Block
    • PL/SQL Function
    • PL/SQL Unwrapper
    • PL/SQL Table
    • PL/SQL ALTER TABLE
    • PLSQL execute immediate
    • Triggers in PL/SQL
    • PL/SQL Collections
    • PL/SQL stored procedure
    • PL/SQL Anonymous Block
    • PLSQL Interview Questions
  • TSQL Basic
    • TSQL
    • What is T-SQL
    • T-SQL Commands
    • T-SQL String Functions
    • TSQL Interview Questions
  • MariaDB
    • MariaDB Versions
    • MariaDB?list users
    • MariaDB Commands
    • MariaDB Server
    • MariaDB? Data Types
    • MariaDB?boolean
    • MariaDB phpMyAdmin
    • MariaDB Mysqldump
    • MariaDB Java Connector
    • MariaDB insert
    • MariaDB UPDATE
    • MariaDB? rename column
    • MariaDB AUTO_INCREMENT
    • MariaDB Timezone
    • MariaDB GROUP_CONCAT
    • MariaDB wait_timeout
    • MariaDB MaxScale
    • MariaDB? with
    • MariaDB? create?table
    • MariaDB? SHOW TABLES
    • MariaDB alter table
    • MariaDB List Tables
    • MariaDB JSON Functions
    • MariaDB Foreign Key
    • MariaDB? trigger
    • MariaDB Grant All Privileges
    • MariaDB Select Database
    • MariaDB? create database
    • MariaDB Delete Database
    • MariaDB List Databases
    • MariaDB Functions
    • MariaDB? TIMESTAMP
    • MariaDB create user
    • MariaDB add user
    • MariaDB show users
    • MariaDB Delete User
    • MariaDB? change user password
    • MariaDB? change root password
    • MariaDB reset root password
    • MariaDB IF
    • MariaDB bind-address
    • MariaDB Transaction
    • MariaDB Cluster
    • MariaDB Logs
    • MariaDB Encryption
    • MariaDB? backup
    • MariaDB Replication
    • MariaDB max_allowed_packet
    • MariaDB? performance tuning
    • MariaDB export database
    • MariaDB? import SQL
  • SQLite
    • What is SQLite
    • SQLite Commands
    • SQLite Data Types
    • SQLite COUNT
    • SQLite Boolean
    • SQLite autoincrement
    • SQLite select
    • SQLite? Bulk Insert
    • SQLite? add column
    • SQLite? concat
    • SQLite BETWEEN
    • SQLite group by
    • SQLite CASE
    • SQLite group_concat
    • SQLite array
    • SQLite? enum
    • SQLite sum
    • SQLite create table
    • SQLite Alter Table
    • SQLite Create Database
    • SQLite Delete
    • SQLite connection string
    • SQLite Database
    • SQLite Describe Table
    • SQLite Show Tables
    • SQLite exit
    • SQLite create index
    • SQLite foreign key
    • SQLite Stored Procedures
    • SQLite Extension
  • DB2
    • DB2? current date
    • DB2 purescale
    • DB2 backup
    • DB2 restore
    • DB2 C Express
    • DB2 Version
    • DB2? Architecture
    • DB2? Data Types
    • DB2? load
    • DB2? order by
    • DB2 date
    • DB2 NVL
    • DB2? update
    • DB2 warehouse
    • DB2 grant
    • DB2 database
    • DB2 VARCHAR
    • DB2? INSERT
    • DB2 LISTAGG
    • DB2 LIKE
    • DB2 TRUNCATE TABLE
    • DB2 LIST TABLES
    • DB2 between
    • DB2? current timestamp
    • DB2? length
    • DB2? bind
    • DB2 limit rows
    • DB2? export
    • DB2 with
    • DB2 Create Table
    • DB2 case statement
    • DB2 CAST
    • DB2 Functions
    • DB2 Date Functions
    • DB2? row_number
    • DB2 trim
    • DB2? Translate
    • DB2 UNION
    • DB2 timestamp
    • DB2? TIMESTAMPDIFF
    • DB2? replace
    • DB2 merge
    • DB2 COALESCE
    • DB2 ISNULL
    • DB2? explain
    • DB2 Join
    • DB2 alter column
    • DB2 rename column
    • DB2? Describe Table
    • DB2? rename table
    • DB2 List Databases
    • DB2 LUW
    • DB2 Query
    • DB2 GROUP BY
    • DB2 TO_DATE
    • View Serializability in DBMS
    • MariaDB Join
    • MariaDB JSON
    • MariaDB? show databases
    • Dataset Normalization
    • MariaDB Max Connections
    • jdbc connection
    • MariaDB GUI

Related Courses

SQL Certification Course

PL/SQL Certification Course

Oracle Certification Course

Footer
About Us
  • Blog
  • Who is EDUCBA?
  • Sign Up
  • Live Classes
  • Corporate Training
  • Certificate from Top Institutions
  • Contact Us
  • Verifiable Certificate
  • Reviews
  • Terms and Conditions
  • Privacy Policy
  •  
Apps
  • iPhone & iPad
  • Android
Resources
  • Free Courses
  • Database Management
  • Machine Learning
  • All Tutorials
Certification Courses
  • All Courses
  • Data Science Course - All in One Bundle
  • Machine Learning Course
  • Hadoop Certification Training
  • Cloud Computing Training Course
  • R Programming Course
  • AWS Training Course
  • SAS Training Course

© 2022 - EDUCBA. ALL RIGHTS RESERVED. THE CERTIFICATION NAMES ARE THE TRADEMARKS OF THEIR RESPECTIVE OWNERS.

EDUCBA
Free Data Science Course

Hadoop, Data Science, Statistics & others

*Please provide your correct email id. Login details for this Free course will be emailed to you

By signing up, you agree to our Terms of Use and Privacy Policy.

EDUCBA
Free Data Science Course

Hadoop, Data Science, Statistics & others

*Please provide your correct email id. Login details for this Free course will be emailed to you

By signing up, you agree to our Terms of Use and Privacy Policy.

Let’s Get Started

By signing up, you agree to our Terms of Use and Privacy Policy.

Loading . . .
Quiz
Question:

Answer:

Quiz Result
Total QuestionsCorrect AnswersWrong AnswersPercentage

Explore 1000+ varieties of Mock tests View more

EDUCBA Login

Forgot Password?

By signing up, you agree to our Terms of Use and Privacy Policy.

This website or its third-party tools use cookies, which are necessary to its functioning and required to achieve the purposes illustrated in the cookie policy. By closing this banner, scrolling this page, clicking a link or continuing to browse otherwise, you agree to our Privacy Policy

EDUCBA

*Please provide your correct email id. Login details for this Free course will be emailed to you

By signing up, you agree to our Terms of Use and Privacy Policy.

Special Offer - All in One Data Science Bundle (360+ Courses, 50+ projects) Learn More