A database is an abbreviation that stands for "database" or "database" (depending on context). In this article, we consider what she / they are, what they are and where they are used. We also discuss whether DBMS and DB are the same or not.
Terminology
A database is called a structured repository of information. A database is also an information model that can accommodate certain data, provided that they are necessarily ordered. Each of us worked with the database at least once, but we could not even guess about it, for example, entering a search query, we turn to a large-scale database for specific information.- , " ". , . , , , , .
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- Hierarchical - relations at the level of "ancestor-descendant", "boss-subordinate."
- Network - a branch from the previous view.
- Object-oriented, which work directly with the appropriate programming methodology (OOP).
Let us consider each of them in more detail, simultaneously dwelling on the basic ideas and concepts of the database.
Is a DB a plate?
Relational databases in their usual representation do not cause difficulties for understanding - these are signs with information. For clarification, you can call for help a very well-known DBMS from Microsoft - "Access", which is part of their usual office suite of applications.
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This type is conveniently used to build information storages of an already ordered structure: for example, a military unit database or file manager. A disadvantage is the impossibility for a node to have more than one ancestor, as well as the complexity of the database logic.
Expanding Communication
Network databases have become a solution to the lack of hierarchical, named just above. The only difference between this type and the previous one was the many-to-many relationship, which in this case manifests itself in the fact that as an ancestor can have many heirs, so they, descendants, can come from several nodes at once.Tabular display method
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