what is meta data?

Question

with reference to data warehousing

Answer 1

Data about data.

Answer 2

It is a data that describe other data. Generally, a set of metadata describes a single set of data, called a resource.

Metadata are of special interest in various fields of computer science, e. g. information retrieval and the semantic web. Although many consider them a powerful tool to bridge the semantic gap, they are criticized severely by others.



Metadata can be stored either internally, i. e. in the same file as the data, or externally, i. e. in a separate file. Both possibilities have advantages and disadvantages:

Internal storage allows transferring metadata together with their data; thus they are always at hand and can be manipulated easily. This method creates high redundancy and does not allow holding metadata together.
External storage allows bundling metadata, e. g. in a database, for more efficient searching. There is no redundancy and metadata can be transferred simultaneously when using streaming. However, as most formats use URIs for that purpose, the method of how the metadata are linked to their data must be treated with care: What if a resource does not have an URI, e. g. resources on a local hard disk or web pages that are created on-the-fly using a content management system? What if metadata can only be evaluated if there is a connection to the WWW, especially when using RDF? How to realize that a resource is replaced by another with the same name but different content?
Moreover there is the question of data format: Storing metadata in a human-readable format such as XML can be useful because users can understand and edit them without any tools at all. On the other side these formats are not optimized for storage capacity, i. e. it may be useful to store them in a binary non-human-readable format instead to speed up transfer and save memory.

Answer 3

As the chorus has already pointed out, the short (and absolutely correct) answer is that it is data about data.

In data warehousing -- or any relational database -- there are a group of system tables that describe the data. For example, the system tables might say that the LASTNAME field in the EMPLOYEE table is a character string of up to fifty characters in length. They might also say that the field is indexed, allows nulls and is not the primary key.

While an individual employee might have a last name of "Jones" or "Smith", that would be the data. The data about the data tells us that all the last names stored are character strings of up to fifty characters in length.

Answer 4

data about data
"a library catalog is metadata because it describes publications"
The term may refer to detailed compilations such as data dictionaries and repositories that provide a substantial amount of information about each data element. It may also refer to any descriptive item about data, such as the content of an HTML meta tag or a title field in a media file.

Meta-data has existed for centuries. Card catalogs and handwritten indexes are examples long before the electronic age.

Although countless articles, magazines and books spell this term as one word, "meta-data" with the hyphen is the proper, generic spelling, because the Metadata company has trademarked the name.

visit
http://computing-dictionary.thefreedictionary.com/metadata

Good Day
http://www.dataconmng.com

Answer 5

Meta data is data that expresses the context or relativity of data. Examples of meta data include data element descriptions, data type descriptions, attribute/property descriptions, range/domain descriptions and process/method descriptions. The repository environment encompasses all corporate meta data resources: database catalogs, data dictionaries and navigation services. Meta data includes name, length, valid values and description of a data element.

Answer 6

Data about Data is called Metadata.

Answer 7

Meta data is data about data.

Answer 8

info about the data

the data could be like an address book. the meta would say when it was crated - how big it is - where it is etc....

Answer 9

meta data is nothing but just tha data about data once you strored data in database you file of database is also stored somewhere so metadata contains infromation about taht file like name,size,type,stored allocation,created date and so many other information

Answer 10

data that describes data