Information, being the basis of various electronic data exchange systems, is organized in a special way and is called databases. To understand this concept, as well as to understand what a database structure is, it is worth considering this phenomenon in more detail.
Most often, the following requirements should be followed when creating a database . It should be easy to process and be compact, devoid of redundant information. In a hierarchical system, elements are arranged in such a way that links between them are formed - child and parent. That is, this information is located higher or lower in relation to a certain object of the system. But one of them is always the main one, with which the whole system begins. As a result of this arrangement of information blocks, a tree-like database structure is formed, which is characteristic of the file system applicable to computers.
Databases distributed on the network have the same characteristics as hierarchical databases. The difference between them is that in the first child elements can have several ancestors.
But before considering in more detail the structure and types, you need to define the concept of a database. What is meant by this term? The simplest definition would be this: a database is a way to organize and store information. There are many types and methods of systematizing information. Each of them has its own target orientation, meets certain requirements. For example, XML data is structured as a tree that has a branched root and nodes. But this is only one type of information storage.
The hierarchical structure of the database is optimized for reading, quick data selection and delivery to the user. But it also has its drawbacks. So, a computer, quite easily performing an operation with a specific folder or file (which are elements of a hierarchical structure), has been scanning the system for viruses for a long time. This shows that such a system is not suitable for quickly sorting information and, if necessary, the process takes a lot of time. The ratio of elements in such a structure is such that the lower the object is, the greater its nesting. The hierarchical relationships between the parent and child elements of the system are affected.
Another classification of databases is noteworthy . It will be given in order to finally clarify the issue of existing methods of storing information. By the nature of the presentation of information, databases are divided into structured (data in the form of symbols), partially structured (textual information) and unstructured (semantic networks). Structured databases have several levels at which information units are located. These include network and hierarchical databases, where links between individual files are specified. If the hierarchical database is like a tree, then the network resembles a network. In this case, the database structure is arranged in such a way that any vertex can lead into it and several links can be between a pair of vertices. So, one file maintains relations with many, as a result of which its type is not fixed. It can be a member of a set of files (between which a link is declared) or an owner.
There is also a relational database model in which the relationships between files are determined dynamically at the moment the query is executed. Databases are divided by the type of information contained in them into factual, documentary and lexicographic.
Thus, databases are a specially structured system, one of the ways of storing information in which can be a tabular form. The totality of several tables that have logical connections between themselves, and create a database.