SlideShare a Scribd company logo
The three level of data modeling, conceptual data model, logical data model, and physical data model, were discussed in prior sections. Here we compare
these three types of data models. The table below compares the different features:
Feature Conceptual Logical Physical
Entity Names ✓ ✓
Entity Relationships ✓ ✓
Attributes ✓
Primary Keys ✓ ✓
Foreign Keys ✓ ✓
Table Names ✓
Column Names ✓
Column Data Types ✓
Below we show the conceptual, logical, and physical versions of a single data model.
Conceptual Model Design Logical Model Design Physical Model Design
We can see that the complexity increases from conceptual to logical to physical. This is why we always first start with the conceptual data model (so we
understand at high level what are the different entities in our data and how they relate to one another), then move on to the logical data model (so we
understand the details of our data without worrying about how they will actually implemented), and finally the physical data model (so we know exactly how to
implement our data model in the database of choice). In a data warehousing project, sometimes the conceptual data model and the logical data model are
considered as a single deliverable.
A Conceptual Data Model
A conceptual data model identifies the highest-level relationships between the different entities. Features of conceptual data model include:
Includes the important entities and the relationships among them.
No attribute is specified.
No primary key is specified.
The figure below is an example of a conceptual data model.
Conceptual Data Model
From the figure above, we can see that the only information shown via the conceptual data model is the entities that describe the data and the relationships
between those entities. No other information is shown through the conceptual data model.
A Logical Data Model
A logical data model describes the data in as much detail as possible, without regard to how they will be physical implemented in the database. Features of a
logical data model include:
Includes all entities and relationships among them.
All attributes for each entity are specified.
The primary key for each entity is specified.
Foreign keys (keys identifying the relationship between different entities) are specified.
Normalization occurs at this level.
The steps for designing the logical data model are as follows:
1. Specify primary keys for all entities.
2. Find the relationships between different entities.
3. Find all attributes for each entity.
4. Resolve many-to-many relationships.
5. Normalization.
The figure below is an example of a logical data model.
Logical Data Model
Comparing the logical data model shown above with the conceptual data model diagram, we see the main differences between the two:
In a logical data model, primary keys are present, whereas in a conceptual data model, no primary key is present.
In a logical data model, all attributes are specified within an entity. No attributes are specified in a conceptual data model.
Relationships between entities are specified using primary keys and foreign keys in a logical data model. In a conceptual data model, the relationships
are simply stated, not specified, so we simply know that two entities are related, but we do not specify what attributes are used for this relationship.
A Physical Data Model
Physical data model represents how the model will be built in the database. A physical database model shows all table structures, including column name,
column data type, column constraints, primary key, foreign key, and relationships between tables. Features of a physical data model include:
Specification all tables and columns.
Foreign keys are used to identify relationships between tables.
Denormalization may occur based on user requirements.
Physical considerations may cause the physical data model to be quite different from the logical data model.
Physical data model will be different for different RDBMS. For example, data type for a column may be different between MySQL and SQL Server.
The steps for physical data model design are as follows:
1. Convert entities into tables.
2. Convert relationships into foreign keys.
3. Convert attributes into columns.
4. Modify the physical data model based on physical constraints / requirements.
The figure below is an example of a physical data model.
Physical Data Model
Comparing the logical data model shown above with the logical data model diagram, we see the main differences between the two:
Entity names are now table names.
Attributes are now column names.
Data type for each column is specified. Data types can be different depending on the actual database being used.

More Related Content

What's hot

Entity Relationship Diagram
Entity Relationship DiagramEntity Relationship Diagram
Entity Relationship Diagram
Siti Ismail
 
Data Visualization1.pptx
Data Visualization1.pptxData Visualization1.pptx
Data Visualization1.pptx
qwtadhsaber
 
Data Warehouse Modeling
Data Warehouse ModelingData Warehouse Modeling
Data Warehouse Modeling
vivekjv
 
Data models
Data modelsData models
Data models
RituBhargava7
 
Lecture 01 introduction to database
Lecture 01 introduction to databaseLecture 01 introduction to database
Lecture 01 introduction to database
emailharmeet
 
Data Quality Strategies
Data Quality StrategiesData Quality Strategies
Data Quality Strategies
DATAVERSITY
 
How to Strengthen Enterprise Data Governance with Data Quality
How to Strengthen Enterprise Data Governance with Data QualityHow to Strengthen Enterprise Data Governance with Data Quality
How to Strengthen Enterprise Data Governance with Data Quality
DATAVERSITY
 
Enterprise Architecture vs. Data Architecture
Enterprise Architecture vs. Data ArchitectureEnterprise Architecture vs. Data Architecture
Enterprise Architecture vs. Data Architecture
DATAVERSITY
 
LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...
LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...
LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...
DATAVERSITY
 
DBMS and its Models
DBMS and its ModelsDBMS and its Models
DBMS and its Models
AhmadShah Sultani
 
Data Governance Takes a Village (So Why is Everyone Hiding?)
Data Governance Takes a Village (So Why is Everyone Hiding?)Data Governance Takes a Village (So Why is Everyone Hiding?)
Data Governance Takes a Village (So Why is Everyone Hiding?)
DATAVERSITY
 
Data visualization in a Nutshell
Data visualization in a NutshellData visualization in a Nutshell
Data visualization in a Nutshell
WingChan46
 
Conceptual vs. Logical vs. Physical Data Modeling
Conceptual vs. Logical vs. Physical Data ModelingConceptual vs. Logical vs. Physical Data Modeling
Conceptual vs. Logical vs. Physical Data Modeling
DATAVERSITY
 
Presentation on Database management system
Presentation on Database management systemPresentation on Database management system
Presentation on Database management system
Prerana Bhattarai
 
Comparison of Relational Database and Object Oriented Database
Comparison of Relational Database and Object Oriented DatabaseComparison of Relational Database and Object Oriented Database
Comparison of Relational Database and Object Oriented Database
Editor IJMTER
 
The Importance of Master Data Management
The Importance of Master Data ManagementThe Importance of Master Data Management
The Importance of Master Data Management
DATAVERSITY
 
Data Modeling PPT
Data Modeling PPTData Modeling PPT
Data Modeling PPT
Trinath
 
Introduction to Data Visualization
Introduction to Data Visualization Introduction to Data Visualization
Introduction to Data Visualization
Ana Jofre
 
Unit1 DBMS Introduction
Unit1 DBMS IntroductionUnit1 DBMS Introduction
Unit1 DBMS Introduction
MUHAMMED MASHAHIL PUKKUNNUMMAL
 
LDM Webinar: Data Modeling & Metadata Management
LDM Webinar: Data Modeling & Metadata ManagementLDM Webinar: Data Modeling & Metadata Management
LDM Webinar: Data Modeling & Metadata Management
DATAVERSITY
 

What's hot (20)

Entity Relationship Diagram
Entity Relationship DiagramEntity Relationship Diagram
Entity Relationship Diagram
 
Data Visualization1.pptx
Data Visualization1.pptxData Visualization1.pptx
Data Visualization1.pptx
 
Data Warehouse Modeling
Data Warehouse ModelingData Warehouse Modeling
Data Warehouse Modeling
 
Data models
Data modelsData models
Data models
 
Lecture 01 introduction to database
Lecture 01 introduction to databaseLecture 01 introduction to database
Lecture 01 introduction to database
 
Data Quality Strategies
Data Quality StrategiesData Quality Strategies
Data Quality Strategies
 
How to Strengthen Enterprise Data Governance with Data Quality
How to Strengthen Enterprise Data Governance with Data QualityHow to Strengthen Enterprise Data Governance with Data Quality
How to Strengthen Enterprise Data Governance with Data Quality
 
Enterprise Architecture vs. Data Architecture
Enterprise Architecture vs. Data ArchitectureEnterprise Architecture vs. Data Architecture
Enterprise Architecture vs. Data Architecture
 
LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...
LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...
LDM Slides: Conceptual Data Models - How to Get the Attention of Business Use...
 
DBMS and its Models
DBMS and its ModelsDBMS and its Models
DBMS and its Models
 
Data Governance Takes a Village (So Why is Everyone Hiding?)
Data Governance Takes a Village (So Why is Everyone Hiding?)Data Governance Takes a Village (So Why is Everyone Hiding?)
Data Governance Takes a Village (So Why is Everyone Hiding?)
 
Data visualization in a Nutshell
Data visualization in a NutshellData visualization in a Nutshell
Data visualization in a Nutshell
 
Conceptual vs. Logical vs. Physical Data Modeling
Conceptual vs. Logical vs. Physical Data ModelingConceptual vs. Logical vs. Physical Data Modeling
Conceptual vs. Logical vs. Physical Data Modeling
 
Presentation on Database management system
Presentation on Database management systemPresentation on Database management system
Presentation on Database management system
 
Comparison of Relational Database and Object Oriented Database
Comparison of Relational Database and Object Oriented DatabaseComparison of Relational Database and Object Oriented Database
Comparison of Relational Database and Object Oriented Database
 
The Importance of Master Data Management
The Importance of Master Data ManagementThe Importance of Master Data Management
The Importance of Master Data Management
 
Data Modeling PPT
Data Modeling PPTData Modeling PPT
Data Modeling PPT
 
Introduction to Data Visualization
Introduction to Data Visualization Introduction to Data Visualization
Introduction to Data Visualization
 
Unit1 DBMS Introduction
Unit1 DBMS IntroductionUnit1 DBMS Introduction
Unit1 DBMS Introduction
 
LDM Webinar: Data Modeling & Metadata Management
LDM Webinar: Data Modeling & Metadata ManagementLDM Webinar: Data Modeling & Metadata Management
LDM Webinar: Data Modeling & Metadata Management
 

Similar to The three level of data modeling

Before you take a gander at particular images, its vital to compre.pdf
Before you take a gander at particular images, its vital to compre.pdfBefore you take a gander at particular images, its vital to compre.pdf
Before you take a gander at particular images, its vital to compre.pdf
aquacare2008
 
Data modeling levels and techniques.docx
Data modeling levels and techniques.docxData modeling levels and techniques.docx
Data modeling levels and techniques.docx
LanLThThy
 
Data modeling levels and techniques.docx
Data modeling levels and techniques.docxData modeling levels and techniques.docx
Data modeling levels and techniques.docx
LanLThThy
 
Data modeling levels and techniques.docx
Data modeling levels and techniques.docxData modeling levels and techniques.docx
Data modeling levels and techniques.docx
LanLThThy
 
1.1 Data Modelling - Part I (Understand Data Model).pdf
1.1 Data Modelling - Part I (Understand Data Model).pdf1.1 Data Modelling - Part I (Understand Data Model).pdf
1.1 Data Modelling - Part I (Understand Data Model).pdf
RakeshKumar145431
 
Data Modeling.docx
Data Modeling.docxData Modeling.docx
Data Modeling.docx
Michuki Samuel
 
database-model group presentation.pptx
database-model group   presentation.pptxdatabase-model group   presentation.pptx
database-model group presentation.pptx
RuksanKarki
 
Student POST  Database processing models showcase the logical s.docx
Student POST  Database processing models showcase the logical s.docxStudent POST  Database processing models showcase the logical s.docx
Student POST  Database processing models showcase the logical s.docx
orlandov3
 
2. Chapter Two.pdf
2. Chapter Two.pdf2. Chapter Two.pdf
2. Chapter Two.pdf
fikadumola
 
Bca examination 2017 dbms
Bca examination 2017 dbmsBca examination 2017 dbms
Bca examination 2017 dbms
Anjaan Gajendra
 
DBMS OF DATA MODEL Deepika 2
DBMS OF DATA MODEL  Deepika 2DBMS OF DATA MODEL  Deepika 2
DBMS OF DATA MODEL Deepika 2
Rai Saheb Bhanwar Singh College Nasrullaganj
 
Database System Concepts AND architecture [Autosaved].pptx
Database System Concepts AND architecture [Autosaved].pptxDatabase System Concepts AND architecture [Autosaved].pptx
Database System Concepts AND architecture [Autosaved].pptx
Koteswari Kasireddy
 
DBMS
DBMSDBMS
Data models
Data modelsData models
Data models
Hira Bukhari
 
Data models
Data modelsData models
Data models
Hira Bukhari
 
chapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdf
chapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdfchapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdf
chapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdf
MisganawAbeje1
 
Data modeling 101 - Basics - Software Domain
Data modeling 101 - Basics - Software DomainData modeling 101 - Basics - Software Domain
Data modeling 101 - Basics - Software Domain
Abdul Ahad
 
Data Modeling Training.pptx
Data Modeling Training.pptxData Modeling Training.pptx
Data Modeling Training.pptx
ssuser23b3eb
 
Dbms unit i
Dbms unit iDbms unit i
Dbms unit i
Arnav Chowdhury
 
activity 1 for module 2.docx
activity 1 for module 2.docxactivity 1 for module 2.docx
activity 1 for module 2.docx
RomarLayco1
 

Similar to The three level of data modeling (20)

Before you take a gander at particular images, its vital to compre.pdf
Before you take a gander at particular images, its vital to compre.pdfBefore you take a gander at particular images, its vital to compre.pdf
Before you take a gander at particular images, its vital to compre.pdf
 
Data modeling levels and techniques.docx
Data modeling levels and techniques.docxData modeling levels and techniques.docx
Data modeling levels and techniques.docx
 
Data modeling levels and techniques.docx
Data modeling levels and techniques.docxData modeling levels and techniques.docx
Data modeling levels and techniques.docx
 
Data modeling levels and techniques.docx
Data modeling levels and techniques.docxData modeling levels and techniques.docx
Data modeling levels and techniques.docx
 
1.1 Data Modelling - Part I (Understand Data Model).pdf
1.1 Data Modelling - Part I (Understand Data Model).pdf1.1 Data Modelling - Part I (Understand Data Model).pdf
1.1 Data Modelling - Part I (Understand Data Model).pdf
 
Data Modeling.docx
Data Modeling.docxData Modeling.docx
Data Modeling.docx
 
database-model group presentation.pptx
database-model group   presentation.pptxdatabase-model group   presentation.pptx
database-model group presentation.pptx
 
Student POST  Database processing models showcase the logical s.docx
Student POST  Database processing models showcase the logical s.docxStudent POST  Database processing models showcase the logical s.docx
Student POST  Database processing models showcase the logical s.docx
 
2. Chapter Two.pdf
2. Chapter Two.pdf2. Chapter Two.pdf
2. Chapter Two.pdf
 
Bca examination 2017 dbms
Bca examination 2017 dbmsBca examination 2017 dbms
Bca examination 2017 dbms
 
DBMS OF DATA MODEL Deepika 2
DBMS OF DATA MODEL  Deepika 2DBMS OF DATA MODEL  Deepika 2
DBMS OF DATA MODEL Deepika 2
 
Database System Concepts AND architecture [Autosaved].pptx
Database System Concepts AND architecture [Autosaved].pptxDatabase System Concepts AND architecture [Autosaved].pptx
Database System Concepts AND architecture [Autosaved].pptx
 
DBMS
DBMSDBMS
DBMS
 
Data models
Data modelsData models
Data models
 
Data models
Data modelsData models
Data models
 
chapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdf
chapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdfchapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdf
chapter 2-DATABASE SYSTEM CONCEPTS AND architecture [Autosaved].pdf
 
Data modeling 101 - Basics - Software Domain
Data modeling 101 - Basics - Software DomainData modeling 101 - Basics - Software Domain
Data modeling 101 - Basics - Software Domain
 
Data Modeling Training.pptx
Data Modeling Training.pptxData Modeling Training.pptx
Data Modeling Training.pptx
 
Dbms unit i
Dbms unit iDbms unit i
Dbms unit i
 
activity 1 for module 2.docx
activity 1 for module 2.docxactivity 1 for module 2.docx
activity 1 for module 2.docx
 

Recently uploaded

OpenID AuthZEN Interop Read Out - Authorization
OpenID AuthZEN Interop Read Out - AuthorizationOpenID AuthZEN Interop Read Out - Authorization
OpenID AuthZEN Interop Read Out - Authorization
David Brossard
 
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slack
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with SlackLet's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slack
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slack
shyamraj55
 
Main news related to the CCS TSI 2023 (2023/1695)
Main news related to the CCS TSI 2023 (2023/1695)Main news related to the CCS TSI 2023 (2023/1695)
Main news related to the CCS TSI 2023 (2023/1695)
Jakub Marek
 
Best 20 SEO Techniques To Improve Website Visibility In SERP
Best 20 SEO Techniques To Improve Website Visibility In SERPBest 20 SEO Techniques To Improve Website Visibility In SERP
Best 20 SEO Techniques To Improve Website Visibility In SERP
Pixlogix Infotech
 
Skybuffer SAM4U tool for SAP license adoption
Skybuffer SAM4U tool for SAP license adoptionSkybuffer SAM4U tool for SAP license adoption
Skybuffer SAM4U tool for SAP license adoption
Tatiana Kojar
 
Energy Efficient Video Encoding for Cloud and Edge Computing Instances
Energy Efficient Video Encoding for Cloud and Edge Computing InstancesEnergy Efficient Video Encoding for Cloud and Edge Computing Instances
Energy Efficient Video Encoding for Cloud and Edge Computing Instances
Alpen-Adria-Universität
 
GraphRAG for Life Science to increase LLM accuracy
GraphRAG for Life Science to increase LLM accuracyGraphRAG for Life Science to increase LLM accuracy
GraphRAG for Life Science to increase LLM accuracy
Tomaz Bratanic
 
Taking AI to the Next Level in Manufacturing.pdf
Taking AI to the Next Level in Manufacturing.pdfTaking AI to the Next Level in Manufacturing.pdf
Taking AI to the Next Level in Manufacturing.pdf
ssuserfac0301
 
HCL Notes and Domino License Cost Reduction in the World of DLAU
HCL Notes and Domino License Cost Reduction in the World of DLAUHCL Notes and Domino License Cost Reduction in the World of DLAU
HCL Notes and Domino License Cost Reduction in the World of DLAU
panagenda
 
UiPath Test Automation using UiPath Test Suite series, part 6
UiPath Test Automation using UiPath Test Suite series, part 6UiPath Test Automation using UiPath Test Suite series, part 6
UiPath Test Automation using UiPath Test Suite series, part 6
DianaGray10
 
Nordic Marketo Engage User Group_June 13_ 2024.pptx
Nordic Marketo Engage User Group_June 13_ 2024.pptxNordic Marketo Engage User Group_June 13_ 2024.pptx
Nordic Marketo Engage User Group_June 13_ 2024.pptx
MichaelKnudsen27
 
Digital Marketing Trends in 2024 | Guide for Staying Ahead
Digital Marketing Trends in 2024 | Guide for Staying AheadDigital Marketing Trends in 2024 | Guide for Staying Ahead
Digital Marketing Trends in 2024 | Guide for Staying Ahead
Wask
 
Building Production Ready Search Pipelines with Spark and Milvus
Building Production Ready Search Pipelines with Spark and MilvusBuilding Production Ready Search Pipelines with Spark and Milvus
Building Production Ready Search Pipelines with Spark and Milvus
Zilliz
 
Monitoring and Managing Anomaly Detection on OpenShift.pdf
Monitoring and Managing Anomaly Detection on OpenShift.pdfMonitoring and Managing Anomaly Detection on OpenShift.pdf
Monitoring and Managing Anomaly Detection on OpenShift.pdf
Tosin Akinosho
 
UI5 Controls simplified - UI5con2024 presentation
UI5 Controls simplified - UI5con2024 presentationUI5 Controls simplified - UI5con2024 presentation
UI5 Controls simplified - UI5con2024 presentation
Wouter Lemaire
 
AI 101: An Introduction to the Basics and Impact of Artificial Intelligence
AI 101: An Introduction to the Basics and Impact of Artificial IntelligenceAI 101: An Introduction to the Basics and Impact of Artificial Intelligence
AI 101: An Introduction to the Basics and Impact of Artificial Intelligence
IndexBug
 
Columbus Data & Analytics Wednesdays - June 2024
Columbus Data & Analytics Wednesdays - June 2024Columbus Data & Analytics Wednesdays - June 2024
Columbus Data & Analytics Wednesdays - June 2024
Jason Packer
 
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfUnlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
Malak Abu Hammad
 
5th LF Energy Power Grid Model Meet-up Slides
5th LF Energy Power Grid Model Meet-up Slides5th LF Energy Power Grid Model Meet-up Slides
5th LF Energy Power Grid Model Meet-up Slides
DanBrown980551
 
Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...
Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...
Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...
saastr
 

Recently uploaded (20)

OpenID AuthZEN Interop Read Out - Authorization
OpenID AuthZEN Interop Read Out - AuthorizationOpenID AuthZEN Interop Read Out - Authorization
OpenID AuthZEN Interop Read Out - Authorization
 
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slack
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with SlackLet's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slack
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slack
 
Main news related to the CCS TSI 2023 (2023/1695)
Main news related to the CCS TSI 2023 (2023/1695)Main news related to the CCS TSI 2023 (2023/1695)
Main news related to the CCS TSI 2023 (2023/1695)
 
Best 20 SEO Techniques To Improve Website Visibility In SERP
Best 20 SEO Techniques To Improve Website Visibility In SERPBest 20 SEO Techniques To Improve Website Visibility In SERP
Best 20 SEO Techniques To Improve Website Visibility In SERP
 
Skybuffer SAM4U tool for SAP license adoption
Skybuffer SAM4U tool for SAP license adoptionSkybuffer SAM4U tool for SAP license adoption
Skybuffer SAM4U tool for SAP license adoption
 
Energy Efficient Video Encoding for Cloud and Edge Computing Instances
Energy Efficient Video Encoding for Cloud and Edge Computing InstancesEnergy Efficient Video Encoding for Cloud and Edge Computing Instances
Energy Efficient Video Encoding for Cloud and Edge Computing Instances
 
GraphRAG for Life Science to increase LLM accuracy
GraphRAG for Life Science to increase LLM accuracyGraphRAG for Life Science to increase LLM accuracy
GraphRAG for Life Science to increase LLM accuracy
 
Taking AI to the Next Level in Manufacturing.pdf
Taking AI to the Next Level in Manufacturing.pdfTaking AI to the Next Level in Manufacturing.pdf
Taking AI to the Next Level in Manufacturing.pdf
 
HCL Notes and Domino License Cost Reduction in the World of DLAU
HCL Notes and Domino License Cost Reduction in the World of DLAUHCL Notes and Domino License Cost Reduction in the World of DLAU
HCL Notes and Domino License Cost Reduction in the World of DLAU
 
UiPath Test Automation using UiPath Test Suite series, part 6
UiPath Test Automation using UiPath Test Suite series, part 6UiPath Test Automation using UiPath Test Suite series, part 6
UiPath Test Automation using UiPath Test Suite series, part 6
 
Nordic Marketo Engage User Group_June 13_ 2024.pptx
Nordic Marketo Engage User Group_June 13_ 2024.pptxNordic Marketo Engage User Group_June 13_ 2024.pptx
Nordic Marketo Engage User Group_June 13_ 2024.pptx
 
Digital Marketing Trends in 2024 | Guide for Staying Ahead
Digital Marketing Trends in 2024 | Guide for Staying AheadDigital Marketing Trends in 2024 | Guide for Staying Ahead
Digital Marketing Trends in 2024 | Guide for Staying Ahead
 
Building Production Ready Search Pipelines with Spark and Milvus
Building Production Ready Search Pipelines with Spark and MilvusBuilding Production Ready Search Pipelines with Spark and Milvus
Building Production Ready Search Pipelines with Spark and Milvus
 
Monitoring and Managing Anomaly Detection on OpenShift.pdf
Monitoring and Managing Anomaly Detection on OpenShift.pdfMonitoring and Managing Anomaly Detection on OpenShift.pdf
Monitoring and Managing Anomaly Detection on OpenShift.pdf
 
UI5 Controls simplified - UI5con2024 presentation
UI5 Controls simplified - UI5con2024 presentationUI5 Controls simplified - UI5con2024 presentation
UI5 Controls simplified - UI5con2024 presentation
 
AI 101: An Introduction to the Basics and Impact of Artificial Intelligence
AI 101: An Introduction to the Basics and Impact of Artificial IntelligenceAI 101: An Introduction to the Basics and Impact of Artificial Intelligence
AI 101: An Introduction to the Basics and Impact of Artificial Intelligence
 
Columbus Data & Analytics Wednesdays - June 2024
Columbus Data & Analytics Wednesdays - June 2024Columbus Data & Analytics Wednesdays - June 2024
Columbus Data & Analytics Wednesdays - June 2024
 
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfUnlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdf
 
5th LF Energy Power Grid Model Meet-up Slides
5th LF Energy Power Grid Model Meet-up Slides5th LF Energy Power Grid Model Meet-up Slides
5th LF Energy Power Grid Model Meet-up Slides
 
Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...
Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...
Deep Dive: AI-Powered Marketing to Get More Leads and Customers with HyperGro...
 

The three level of data modeling

  • 1. The three level of data modeling, conceptual data model, logical data model, and physical data model, were discussed in prior sections. Here we compare these three types of data models. The table below compares the different features: Feature Conceptual Logical Physical Entity Names ✓ ✓ Entity Relationships ✓ ✓ Attributes ✓ Primary Keys ✓ ✓ Foreign Keys ✓ ✓ Table Names ✓ Column Names ✓ Column Data Types ✓ Below we show the conceptual, logical, and physical versions of a single data model. Conceptual Model Design Logical Model Design Physical Model Design We can see that the complexity increases from conceptual to logical to physical. This is why we always first start with the conceptual data model (so we understand at high level what are the different entities in our data and how they relate to one another), then move on to the logical data model (so we
  • 2. understand the details of our data without worrying about how they will actually implemented), and finally the physical data model (so we know exactly how to implement our data model in the database of choice). In a data warehousing project, sometimes the conceptual data model and the logical data model are considered as a single deliverable. A Conceptual Data Model A conceptual data model identifies the highest-level relationships between the different entities. Features of conceptual data model include: Includes the important entities and the relationships among them. No attribute is specified. No primary key is specified. The figure below is an example of a conceptual data model. Conceptual Data Model From the figure above, we can see that the only information shown via the conceptual data model is the entities that describe the data and the relationships between those entities. No other information is shown through the conceptual data model.
  • 3. A Logical Data Model A logical data model describes the data in as much detail as possible, without regard to how they will be physical implemented in the database. Features of a logical data model include: Includes all entities and relationships among them. All attributes for each entity are specified. The primary key for each entity is specified. Foreign keys (keys identifying the relationship between different entities) are specified. Normalization occurs at this level. The steps for designing the logical data model are as follows: 1. Specify primary keys for all entities. 2. Find the relationships between different entities. 3. Find all attributes for each entity. 4. Resolve many-to-many relationships. 5. Normalization. The figure below is an example of a logical data model.
  • 4. Logical Data Model Comparing the logical data model shown above with the conceptual data model diagram, we see the main differences between the two: In a logical data model, primary keys are present, whereas in a conceptual data model, no primary key is present. In a logical data model, all attributes are specified within an entity. No attributes are specified in a conceptual data model. Relationships between entities are specified using primary keys and foreign keys in a logical data model. In a conceptual data model, the relationships are simply stated, not specified, so we simply know that two entities are related, but we do not specify what attributes are used for this relationship.
  • 5. A Physical Data Model Physical data model represents how the model will be built in the database. A physical database model shows all table structures, including column name, column data type, column constraints, primary key, foreign key, and relationships between tables. Features of a physical data model include: Specification all tables and columns. Foreign keys are used to identify relationships between tables. Denormalization may occur based on user requirements. Physical considerations may cause the physical data model to be quite different from the logical data model. Physical data model will be different for different RDBMS. For example, data type for a column may be different between MySQL and SQL Server. The steps for physical data model design are as follows: 1. Convert entities into tables. 2. Convert relationships into foreign keys. 3. Convert attributes into columns. 4. Modify the physical data model based on physical constraints / requirements. The figure below is an example of a physical data model. Physical Data Model
  • 6. Comparing the logical data model shown above with the logical data model diagram, we see the main differences between the two: Entity names are now table names. Attributes are now column names. Data type for each column is specified. Data types can be different depending on the actual database being used.