RDBMS
The RDBMS Stands for Relational Database Management System . All the Modern database systems are used this RDMS model.
In RDBMS data are stored in Tables. A Table is a collection of related data and it is stored in rows and columns
Relational Data Model
The Relational data model used to represent the data as a two dimensional table called Relations.
Example
The following Example shows the Employee Relation
Attributes / Field
The Top of row in a Relation called Attributes. Attributes are simply called as Fields. A field is a column in a table that is designed to maintain specific information about every record in the table.
In the above example EmployeeId, EmployeeName and the Department are the Attributes of the relation table Employee
Schemas
The name of the relation and the set of attributes or fields for a relation called Schema for that relation.
For the above example,
The Schema for the relational table Employee is
EmployeeId, EmployeeName, Department)
Here Employee is the name of the table and EmployeeId, EmployeeName and Department are the Attributes of the Relational table Employee.
Tuples / Rows / Records
Each row of a relation other than the Attributes (Top of the row in a relation table) are called Tuples. A record is each individual entry that exists in a table. For example there are 3 records in the above Employee table.
101, Martin and Production is the one tuple of the attributes EmployeeId, EmployeeName and Department for the relation Employee.
And it written as,
(101, Martin, Production)
or in the table format
the following are the tuples or records of the table Employee
The RDBMS Stands for Relational Database Management System . All the Modern database systems are used this RDMS model.
In RDBMS data are stored in Tables. A Table is a collection of related data and it is stored in rows and columns
Relational Data Model
The Relational data model used to represent the data as a two dimensional table called Relations.
Example
The following Example shows the Employee Relation
| Id | EmployeeName | Department |
|---|---|---|
| 101 | Martin | Production |
| 102 | Tom | Sales |
| 103 | Ann | Human Resource |
Attributes / Field
The Top of row in a Relation called Attributes. Attributes are simply called as Fields. A field is a column in a table that is designed to maintain specific information about every record in the table.
In the above example EmployeeId, EmployeeName and the Department are the Attributes of the relation table Employee
Schemas
The name of the relation and the set of attributes or fields for a relation called Schema for that relation.
For the above example,
The Schema for the relational table Employee is
EmployeeId, EmployeeName, Department)
| Id | EmployeeName | Department |
|---|
Tuples / Rows / Records
Each row of a relation other than the Attributes (Top of the row in a relation table) are called Tuples. A record is each individual entry that exists in a table. For example there are 3 records in the above Employee table.
101, Martin and Production is the one tuple of the attributes EmployeeId, EmployeeName and Department for the relation Employee.
And it written as,
(101, Martin, Production)
or in the table format
| 101 | Martin | Production |
the following are the tuples or records of the table Employee
| 101 | Martin | Production |
| 102 | Tom | Sales |
| 103 | Ann | Human Resource |
