Database

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PREPARATORIA NO. 8

DATABASES

Stage 1

DIAGNOSTIC ACTIVITY

Teacher's name: Ana Laura Carmona Martinez

Name: Talina Denisse Alvarado Estrada

Group: 351

I.D: 1739613

HISTORY OF THE DATABASES

The term database was first heard at a symposium in California, they had its origins in 1960 to 1962, when the machines began using encoding information on punch cards through holes. Databases are created with the aim of storing large amounts of data previously stored in books, which were slow, expensive and complex (any update to perform, had to be done in each of the books that appeared this information to change). [pic 3]

To a first approximation, we can say that a database is a collection of related information is grouped or structured. From the IT perspective, a database is a system consisting of a set of data stored on discs that allow direct access to them and a set of programs that manipulate that data set. The origin of the database goes back to ancient times where there were already libraries and all kinds of records. Besides also they used to gather information about crops and censuses. Subsequently, the use of databases developed from the needs of storing large amounts of information or data. Especially since the advent of the first computers, the concept of databases has always been linked to the computer.

In 1884 Herman Hollerith created automatically punch card machine, being named the first statistical engineer in history. At that time, the census is carried out manually. In this situation, Hollerith began work on designing a machine or censadora tabulator based on punched cards.

Another way to explain what is simply is: The "database" (BD) are an indispensable tool in today's information society, its usefulness is due not only to a set of data stored in a particular form in a BD there are a number of elements that help to systematically organize, relate, protect, and manage data efficiently.

Before the current concepts of BD appear, and tools that allow for efficient and proper administration, data is stored in files called planes which had no structure, only fields and records or rows and columns were known. The origin of the BD faces the need to store large amounts of information for future reference.

Different forms dare storage time.

EVOLUTION

In the era of the sixties, computer prices fell for the private companies could acquire; giving way to the use of the discs, which was very effective in the time ahead, because from this support was available the information directly, without having to know the exact location of the data became popular. At this time he was begun earlier generations of network databases and hierarchical databases, as it was possible to save data structures in lists and trees. Another major achievement of the sixties was the alliance of IBM and American Airlines SABRE to develop an operating system that handled the flight booking transactions and information on the passengers of American Airlines. And later in the same decade, he conducted the development of the IDS developed by Charles Bachman (who was part of the CODASYL) involved the creation of a new type of system database known as network model that allowed the creating a standard in database systems through the creation of new languages of information systems. CODASYL (Conference on Data Systems Languages) was a consortium of computer industries that were aimed at regularizing a standard programming language that could be used in many computers. With regard to the seventies, Edgar F. Codd, English computer scientist known for his contributions to the theory of relational databases, defined the relational model at the same time issued a series of rules for relational database systems through his article "a relational Model of data for Large shared Data Banks". This gave way to the birth of the second generation Managers Database Systems.

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