Simply put metadata is data about data. As simple as it sounds, metadata is vital for database management. In order for a database to be designed and created, metadata must be defined.
When you create a database, you may create fields such as first name, address, telephone, customerid. As for metadata, it will describe in details the type of field is Telephone by setting it as a number with X amount of characters or First Name may not contain integers or a max of 50 characters may be set.
Metadata may also set security measures in place by defining who's allowed to access which data or which data may be changed. In order for a database to be managed, there must a clear understanding of its metadata. Without this knowledge, data may have no meaning or integrity may not exist.
For example, in a relational database, metadata will define tables including their name number of records or rows within each one. In addition, it may also define columns in each of these tables and define the type of data to be used in each field. It's similar as to creating a catalog summary of a full database.
References:
1) http://en.wikipedia.org/wiki/Metadata
2) http://www.ukoln.ac.uk/metadata/presentations/2006/rsc-northwest/discovery.pdf
3) http://linktionary.com/m/metadata.html
When you create a database, you may create fields such as first name, address, telephone, customerid. As for metadata, it will describe in details the type of field is Telephone by setting it as a number with X amount of characters or First Name may not contain integers or a max of 50 characters may be set.
Metadata may also set security measures in place by defining who's allowed to access which data or which data may be changed. In order for a database to be managed, there must a clear understanding of its metadata. Without this knowledge, data may have no meaning or integrity may not exist.
For example, in a relational database, metadata will define tables including their name number of records or rows within each one. In addition, it may also define columns in each of these tables and define the type of data to be used in each field. It's similar as to creating a catalog summary of a full database.
References:
1) http://en.wikipedia.org/wiki/Metadata
2) http://www.ukoln.ac.uk/metadata/presentations/2006/rsc-northwest/discovery.pdf
3) http://linktionary.com/m/metadata.html
