There are many databases. To understand what they are, you need to consider their contents. But there is one small useful detail - metadata. This is what summarizes all the information available. What were they designed for and why are they used?
What is metadata?
It should be noted that a single formulation of this concept does not exist. So metadata is the common name for database information.
Four notations of this term are mainly used:
- May imply sub-channel information about the data used.
- So called characteristics that describe the essence. They are necessary to search, identify, evaluate and manage values in the database. This is also the name of an important set of a certain number of structured descriptions provided in an acceptable form and available in an explicit form, so you can find the necessary object. A similar formulation is used in cases where it is necessary to search for entities, resources and objects.
- Data from a common formal system that describes the properties of a particular information store.
- Information about the characteristics of the web page (when it was created, who is its author).
The difference between data and metadata
How are they distinguished? The fact is that an unambiguous separation is usually impossible. Why? Let's take a closer look at an example:
- Something can act in both roles. For example, the title of an article can be considered both as an element of metadata and as information that is transmitted to the reader.
- The ability to swap places. Suppose someone wrote a poem. It represents data. The composer, relying on words, created a musical composition and attached this text. In this case, it turns into metadata. It all depends on the use. In general, such cases are possible due to the perception of a certain point of view on the basis of their judgments (here the namespace and reference frame play a role).
- The ability to create meta ... metadata focusing on the axiom of choice. This follows from the fact that almost any information can be created its own system of characteristics.
File metadata in computers
They found their application in automated workflows. If some program can work with the content and data structure, then they can be converted into another type of information, which allows you to free users from many inconvenient and routine actions.
An example is the development that allows you to view graphic images with different extensions. You can also recall the various sound recordings, films, and many other things.
World Wide Web Metadata
On the Internet, with their help, the necessary useful information is searched among huge data arrays. From this point of view, metadata that are created manually are of great value because of their meaningfulness. As this type of information can be keywords, tags and a number of other elements. Metadata is what briefly talks about the site. When conducting a search engine analysis of several sites, if they reveal the same thematic words on them, then their mutual reference to each other will be more important than from conventional sites.
Metadata Classification
How are they distinguished? Basically, the classification is carried out according to one of two principles:
- Content. Metadata is used to describe a file, resource or its contents (for example, the heading is “how to cook potatoes”).
- By accessory. I can use metadata to inform about the whole or its component. So, the name of the film refers to all of it, and the description of the episode informs only about a certain part.
If metadata is a collection of dependencies on logical inference capabilities, then in this case they are divided into 3 types:
- Raw data. The basis of information support.
- Metadata describing the content. They, in turn, are also used.
- Metadata with which you can make a logical conclusion.
These types of metadata exist.
The three most sought after classes
We offer you to get acquainted with three classes that are now widely used:
- Internal metadata. This is information that describes the component parts of things, their structure and what it is. An example is the size and format of a file.
- Administrative metadata. Required for information processing processes, as well as for the appointment of things. For example, who is the author, editor, when the file was created.
- Descriptive Metadata. They are used to characterize the nature of the file and its attributes (which category it belongs to, what is it connected with).
Metadata format
This is the name of the standard that is used to conduct a formal description of a certain category of resources (entities, objects, and the like).
Usually it has a certain set that characterizes the object in question. For this, attributes, properties, metadata elements are used.
They are classified by the scope and details of the described resources.
Possible problems
When can a metadata error occur? Lack of necessary information or restriction of access are the main causes of the problems that arise.
Also, an error loading metadata appears in cases where the file is, but it is damaged. The main reasons for this condition are three: the deterioration of equipment, the harmful effects of certain programs (usually computer viruses) and the incorrect completion of a document, which is why the data was saved incorrectly.
Accordingly, the importance of metadata in the classification and systematization of network information is difficult to overestimate. Therefore, those who want to optimize their own site simply need knowledge about them.