The database is an integrated collection of logically related documents or files, which brings together a set of items in the overall records that for many applications. The database is a collection of information organized in such a way that it is easy to read, manage and update.
The data in the database is organized based on a database model. The model is most used today is a relational model. Other models such as the hierarchical model and network model, the use of a clearer representation of relations.
Architecture
Depending on the intended purpose of a number of database platforms in use. Many databases use a combination strategy. On-line transaction processing systems (OLTP) often use the line-oriented data store architecture, while the database and retrieve specific applications such as Google BigTable or bibliographic database (library catalog systems) can use the column-oriented DBMS architecture.
Document-oriented, XML, you know, databases, and the frame and RDF stores (also known as triple-stores), can also be used in combination with the implementation of these platforms.
Finally, it should be noted that not all databases or a database to a scheme (schema-less databases).
For many years, the database industry is dominated by general-purpose database systems for a wide range of functions that apply a lot to offer, if not most cases, today's data processing. Cleaned the extensible data types, Postgre SQL pioneer project, so that a very large number of applications are developed.
There are also other types of database, which can not be regarded as relational databases.
Database management systems
Database management system (DBMS) is software that organizes data to be stored. It regulates the establishment, maintenance and use of the database tables of organization and its users. This allows companies to check the organization's database development site in the hands of Database Administrators (DBA) and other professionals. Large systems, DBMS and other software users to store and retrieve data in a structured way.
Database management systems are classified into the database model that they support, such as a network model or relational model. The model tends to define the query language, that there is access to the database. General Query Language SQL, SQL syntax, however, and the function of different DBMS to another. Much of the internal engineering DBMS does not depend on the data model and is related to the management of factors such as the performance hit, integrity and repair of hardware problems. In these areas there are major differences between the products.
Relational database management system (RDBMS) implementing the relational properties of the model. In this context, "Date of information principle" says: "The information content of the database are represented in only one way. The clear values in column positions (attributes) and relations between the rows (tuples). Therefore, no clear reference to related tables."
Database Models
Post-relational database models
Products for the model and the relational data model may be classified as relational. Data model for relations between the products include, but are not limited to information principle, which requires that all information is represented in the data values in relations.
Some of these concepts effectively integrated into the extension of the relational model, relational model technologies earliest. For example, they allow directed graph represented by the nodes in the trees.
Some of the products to implement such models are constructed by extending the relational database systems for non-relational properties. Others, however, received much the same thing by adding relational features of pre-relational systems. Paradoxically, it is historically pre-relational products, such as mumps and choose, a plausible claim that after their current relational architecture.
Object database models
In recent years, object-oriented paradigm to database technology, creating various new types of programming model known as object databases. These databases attempt to bring the world closer to the application programming and database of The World, in particular by ensuring that the database system uses the same type of application program. This is necessary in order to avoid overhead (sometimes referred to as impedance mismatch) of converting information between its representation in the database (such as tables, rows), and its representation in the application program (typically as objects). Although the main purpose of the intentions of the idea of an object database programming, such as encapsulation and polymorphism, the world's databases.
Different ways of trying to maintain the database objects. Some products have approached the problem of application programming end, by an object manipulated by the program permanent. It is also usually necessary to include the type Query Language, as a normal programming languages is not possible to objects based on their information content can be obtained. Others have attacked the problem at the end of the database, defining the object-oriented data model for the database and identify database programming language that allows any programming skills and the traditional query facilities.
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