Metadata
Understanding Metadata
- Metadata is the data providing information about other data. In other words, it’s data about data.
- It serves to provide detailed information about a data item’s content, condition and other characteristics.
- For instance, in a music file, metadata may include the song title, artist name, album name, and year of release.
Types of Metadata
- Descriptive metadata is used for discovery and identification. It includes elements such as title, author, and keywords.
- Structural metadata gives a description of how the components of an object are organised.
- Administrative metadata provides information that helps manage a resource, such as when and how it was created, file type and other technical information, and who can access it.
Uses of Metadata
- Metadata makes it easier for data to be located and retrieved. This is useful in large databases, digital libraries, and on the internet where a search engine needs to find relevant data.
- It assists in understanding complex files, providing detailed information, and helping to organise electronic resources.
- Metadata also provides a digital identification for files enabling easy sharing and distribution of data across different systems.
Metadata in File Systems
- Metadata is used in file systems to manage files and directories.
- A file’s metadata could include information such as its size, creation date, modification date, and permissions.
- In file systems, metadata is used for file system management, data recovery, and ensuring data integrity.
Metadata in Database Management Systems
- In Database Management Systems (DBMS), metadata is stored in the system catalogs and describes the structure of the individual databases.
- By storing metadata in system catalogs, a DBMS can automate many tasks, including creating views, performing transactions, and optimising queries.