Database is a set of logical data elements associated with each other and the relationship of sports and the database consists of a table and one or more of a table. The table consists of records (Record) or more of the record and the record consists of a field (Field) or more of the field is an example of the record: the registry for a particular staff member is composed of several fields such as employee number – name of the employee – the grade of staff – the date of appointment – salary – Section of him … and so on from employee data stored in a computer in an orderly manner, where the program (computer) is called the database engine (Database Engine) to facilitate handling and search the data, and enable the user to add and modify them ..
Data is retrieved using commands from the language of the query (Query language), where is information to assist in the process of decision-making.
Database management system (Database Management System (DBMS)) is a program through which the retrieved data, or add or modify, or delete it, where the program a link between a user and the database engine to perform that task.
In case there is a relationship Maicon (Relation) between the database tables is called the system of relational databases (Relational Database Management System – RDBMS) basic objective of the database is to focus on how to organize the data and not on specific applications. That the key goal of the database designer is to design data that are free from redundancy and can be retrieved and modified and add it without the problems that can occur with a frequency in it. This is done by creating three levels of abstraction, or forms of databases, called normalization models (Normalizing Forms), and are intended to make the combination of data closer to the nature of the taxonomic.
There are combinations of databases by type of mathematical relationship between the data, including:
Relational structure: the adoption of a specific relationship between the data elements, such as being based on the value of the sum of two components. This installation is the most successful structures in place in the world of computer databases, because given the diversity in the type of relationship between the data, because the likelihood of the implementation of the relations in which more than any other structures.
Structural composition: the adoption of the organizational structure of the relationship between the data elements, such as having two components are classified under a single item or subordinate to him.
Hierarchical structure: the adoption of the relationship between the data elements of the pyramid, such that each component is responsible for only one item and nothing more.
[Edit] environments databases
A Database Management System (DBMS) is a set of computer programs that controls the creation, maintenance, and the use of the database with computer as a platform or of an organization and its end users. It allows organizations to place control of organization-wide database development in the hands of database administrators (DBAs) and other specialists. A DBMS is a system software package that helps the use of integrated collection of data records and files known as databases. It allows different user application programs to easily access the same database. DBMSs may use any of a variety of database models, such as the network model or relational model. In large systems, a DBMS allows users and other software to store and retrieve data in a structured way. Instead of having to write computer programs to extract information, user can ask simple questions in a query language. Thus, many DBMS packages provide Fourth-generation programming language (4GLs) and other application development features. It helps to specify the logical organization for a database and access and use the information within a database. It provides facilities for controlling data access, enforcing data integrity, managing concurrency controlled, restoring databas
he database is a collection of objects
Objects are a collection of objects as follows:
1 – tables:
Most important of these objects because the table is the file containing the complete data
These are the tables of the group in a single file And a table contains multiple rows and columns and columns
These are the fields of information to be included within the table for their conservation
We can link all these tables using the primary key to facilitate We have to reach as soon as possible.
2 – Information:
A specific group or unfiltered or filtered from the table according to the conditions or certain characteristics.
3 – models:
A form that placed him any data to put the data properly In a coordinated manner from specific tables we can also introduce data on this form of this table.
4 – reports:
Form printed on the printer.
5 – macros:
The set of actions recorded through a specific process to accomplish specific process.
6 – modules:
Small programs on the performance of something specific When you click on any particular button.
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