FORUM ON WEEK 4

Schema

Schema

by Fatema Tuj Johora -
Number of replies: 13

What is ER model?? Why do we use it??

What is schema??

In reply to Fatema Tuj Johora

Re: Schema

by Renesa Bente Maula -
ER model: ER model stands for an Entity-Relationship model. This model is used to define the data elements and relationships for a specified system. It develops a conceptual design for the database. It also develops a very simple and easy-to-design view of data. We use it to sketch out the design of a database.
Schema: The design of a database is called the schema.
In reply to Fatema Tuj Johora

Re: Schema

by Sajib Dhali -
ER model:An entity–relationship model (or ER model) describes interrelated things of interest in a specific domain of knowledge. A basic ER model is composed of entity types (which classify the things of interest) and specifies relationships that can exist between entities (instances of those entity types)

Scema:The design of a database is called the schema.
In reply to Fatema Tuj Johora

Re: Schema

by Abir Mahmud -
ER Diagrams are most often used to design or debug relational databases in the fields of software engineering, business information systems, education and research. ... ER diagrams also are often used in conjunction with data flow diagrams (DFDs), which map out the flow of information for processes or systems.
In reply to Fatema Tuj Johora

Re: Schema

by Ema Yasmin -
ER model: ER model stands for an Entity-Relationship model. This model is used to define the data elements and relationships for a specified system. It develops a conceptual design for the database. It also develops a very simple and easy-to-design view of data. We use it to sketch out the design of a database.
Schema: The design of a database is called the schema.
In reply to Fatema Tuj Johora

Re: Schema

by Md. Khadamul Islam -
Entity Relationship Model (ER Modeling) is a graphical approach to database design. It is a high-level data model that defines data elements and their relationship for a specified software system. An ER model is used to represent real-world objects.
An entity-relationship diagram, or ER diagram, is essential for modeling the data stored in a database. It is the basic design upon which a database is built. ER diagrams specify what data we will store: the entities and their attributes. They also show how entities relate to other entities.
An entity relationship diagram (ERD) shows the relationships of entity sets stored in a database. By defining the entities, their attributes, and showing the relationships between them, an ER diagram illustrates the logical structure of databases. ER diagrams are used to sketch out the design of a database.
In reply to Fatema Tuj Johora

Re: Schema

by Ripon Mondal -
The ER model defines the conceptual view of a database. It works around real-world entities and the associations among them. At view level, the ER model is considered a good option for designing databases.

A database schema is an abstraction used to represent the storage of data in a database. It not only describes the organization of data but also represents the relationship between various tables in a database.
In reply to Fatema Tuj Johora

Re: Schema

by Md.Yesmot Uddin Majumder Inan -
ER model: ER model stands for an Entity-Relationship model. This model is used to define the data elements and relationships for a specified system. It develops a conceptual design for the database. It also develops a very simple and easy-to-design view of data. We use it to sketch out the design of a database.
Schema: The design of a database is called the schema.
In reply to Fatema Tuj Johora

Re: Schema

by Sweety Islam -
ER Diagrams are most often used to design or debug relational databases in the fields of software engineering, business information systems, education and research. ... ER diagrams also are often used in conjunction with data flow diagrams (DFDs), which map out the flow of information for processes or systems.

Schema:The term "schema" refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database.
In reply to Fatema Tuj Johora

Re: Schema

by Mehedi Hasan Shaon -
Entity-Relationship Model is a graphical approach to database design. It is a high-level data model that defines data elements and their relationship for a specified software system. An ER model is used to represent real-world objects.

An Entity is a thing or object in the real world that is distinguishable from the surrounding environment. For example, each employee of an organization is a separate entity. Following are some of the major characteristics of entities.

The term "schema" refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas called integrity constraints imposed on a database.
In reply to Fatema Tuj Johora

Re: Schema

by Md.Mehedi Khan Pranto -
ER Diagrams are most often used to design or debug relational databases in the fields of software engineering, business information systems, education and research. ... ER diagrams also are often used in conjunction with data flow diagrams (DFDs), which map out the flow of information for processes or systems

The database schema is its structure described in a formal language supported by the database management system. The term "schema" refers to the organization of data as a blueprint of how the database is constructed
In reply to Fatema Tuj Johora

Re: Schema

by shajibur rahman Bappy -
An entity relationship diagram (ERD) shows the relationships of entity sets stored in a database. ... By defining the entities, their attributes, and showing the relationships between them, an ER diagram illustrates the logical structure of databases. ER diagrams are used to sketch out the design of a database.


schema is a set of formulas (sentences) called integrity constraints imposed on a database.
In reply to Fatema Tuj Johora

Re: Schema

by Asma Azim Abir -

ER model

Entity-Relationship Model (ER Modeling) is a graphical approach to database design. It is a high-level data model that defines the data components and their relationships for specific software systems. Basically, it is used to represent real-world objects. 

Now, this is a very important question that, why use ER modeling when we can create a database and all its objects without ER modeling? One of the challenges when designing a database is that designers, developers, and end-users look at data and its usage differently. If this situation is not checked, we can create a database system that does not meet user requirements. Communication tools meant by all (both technical as well as non-technical users) stakeholders are important in creating database systems that meet user needs. ER models are examples of such tools. ER diagrams increase user productivity because they can be easily translated into related tables.

 

Schema

A database schema is a skeletal structure that represents a logical view of the entire database. It defines how data is organized and how relationships are linked between them. It creates all the constraint formulas that need to be applied to the data. A database schema determines its entities and the relation between them. It contains identifying details of the database, which can be shown by schema diagrams. It is a database designer who designs schemas to help programmers understand the database and make it useful.

 


In reply to Fatema Tuj Johora

Re: Schema

by Ashraful islam 181-15-1921 -
ER Diagram: ER Diagrams are most often used to design or debug relational databases in the fields of software engineering, business information systems, education, and research. ER diagrams also are often used in conjunction with data flow diagrams (DFDs), which point out the flow of information for processes or systems.

Schema: The term "schema" means the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database.