DATABASE DATABASE

The word database was heard for the first time in 1963 at a symposium in California USA.Una database can be defined as a set of related information that is pooled or estructurada.Desde the standpoint of computer, the database is a system formed by a set of data stored on disks that allow direct access to them and a set of programs that manipulate the whole work was carried datos.Este order to learn more about a database, their characteristics, uses, structures, designs, otros.Una between database is of great importance in the rhythm of life we have at the present time because it is accelerating the pace at the time conducting a search information.

Some concepts of databases: Databases: Data collection is the apparent use by the system applications of a particular empresa.Base Data is a set of related information that is structured or clustered. A file itself is not a database, but rather how it is organized is the information that leads to the base of datos.

Base Data: collection of data organized to service many applications at the same time to combine the data so that they appear to be in a single location.

2. Design of a database There are different ways of organizing information and represent the relationships between data in a database. Systems DBAs conventional use of the three models a logical database to keep track of the entities, attributes and relationships. The three main models of logical databases are hierarchical, network and relational. Each logical model has certain advantages and certain processing advantages for business. Hierarchical Data Model: A kind of logical model database has a tree structure. A record divided into segments that are interconnected in parent-child relationships and more. The first systems DBAs were hierarchical. May represent two types of relationships between data: relationships one by one and one-to-many relationships Network data model: It is a variation of the hierarchical data model. In fact the database may result in a hierarchical network and vice versa in order to optimize the speed and convenience of processing. While describing the hierarchical structures of many to many relationships. Relational model of data: The most recent of these models, overcomes some of the limitations of the other two. The relational data model represents all data in the database as a simple two-dimensional tables called relations. Tables are similar to flat files, but information on more than one file can be easily extracted and combined.

3. Creating a database To create a base must be made two years of design: design a logical and a physical. The logical design of a database is an abstract model of the database from a business perspective, while the physical design shows how the database is actually stored in the storage device for direct access. The physical design of the database is carried out by experts in databases, while the logical design requires a detailed description of the information needs of the business of business end users from the current base. Ideally, the design of the database is part of an overall effort of planning level data institucional.El logical design of the database describes the elements in the database are to be grouped. The design process identifies relationships between data elements and the most efficient way of grouping to meet the reporting requirements. The process also identifies redundant elements and groupings of data elements that are required for specific applications programs. Groups of data are organized, streamlined and refined until an overall picture of the logical relationships between all elements in the database arise. Documentary databases: These are derived from the need to have all the information in the workplace and minimize the times of access to such information, although frequently used, are not structured properly. This is because wing source of information is varied (reports, notes, various newspapers, magazines, many more. Distributed databases is that it is stored in more than a physical place.