Metadata
Metadata can he defined as data about data. It is used to describe the properties and characteristics of some other data. Metadata describes the size, format and other characteristics of data. It also includes the rules and constraints about data.
Example:
When you create a table, you specify the data type, size, format and other constraints for entering data in different fields of the table. This is metadata of the table. It describes the properties of the data to be stored in the table. Metadata is very important to ensure the integrity of the data.
Example of Metadata
| Field Name | Data Type | Length | Description | Constant |
| Roll No | Integer | 3 | Roll No of Student | Value from 1 to 100 |
| Name | Alphabetic | 50 | Name of the Student | |
| Address | Alphanumeric | 100 | Address of the Student | |
| Alphanumeric | 25 | Email of the Student | Must Contain @ and | |
| Phone | Alphanumeric | 25 | Phone of the Student |
Example of a Database Table
| Roll No | Name | Address | Phone | |
| 1 | John | London | john@netmail.com | 58264726 |
| 2 | William | New York | willi@mail.com | 98524679 |