The Importance of Databases
Databases
With the great and massive development in the technologies used, and with the increase in reliability and reliance on the Internet, it was necessary for developers to develop a data portfolio in a way through which information can be employed in the best and easiest form; Data is very necessary, especially today. As processing it leads to giving results at maximum speed to business owners, whereby they can, through this processed data, make appropriate decisions for them in their various businesses and jobs.
The concept of the database is no different from the concept of the personnel data record found in the human resources department, as it consists of logical tables interconnected with each other through logical relationships written in a specific programming language, and each table consists of a group of fields linked to each other in a logical way to facilitate the process of retrieval Information and request it from the database through programmatic commands
The importance of databases
Databases are of great importance in different businesses, and their importance stands out in many points, including: Databases greatly help speed up the process of accessing the data they contain. Various works in the future
Databases greatly facilitate the process of modifying this data in the future, and greatly facilitate the process of making the necessary updates, in addition to facilitating addition or deletion operations. Databases help answer any question or inquiry directly related to the data that has been saved and stored within these rules. , and at any time
It helps to coordinate and group huge data in a hierarchical manner to facilitate its management and retrieval.
? Databases or file system
Databases are characterized by ease of storage, speed, and reduction of useless information. As for the file system, we store it in a difficult way, and it requires a very large space for storage and difficulty in finding the required files quickly and accurately, and countless others, and you can go to Google and write in the search engine why to use database to obtain the required information
Database languages
Databases are written in different languages and programs, such as MySQL, Microsoft Access, PHP, and Python. There are also different environments for building databases, the most important of which are Oracle, Firebird, Postgres, Sybase, Microsoft SQL, Informix, and many other environments. Database instructions One of the most popular languages used in building databases is SQL (Structured Query Language). SQL has a set of instructions or commands that can be divided into three groups according to their nature:
DML: Data Manipulation Language, and it has the following instructions:
SELECT Returns some records from one or more tables
INSERT to create records
DELETE to delete records
UPDATE to update the records
DDL: Data Definition Language, and it has the following instructions:
CREATE to create a table, views, index, or any other object
DROP to delete a table or other object
ALTER To modify a table or any other purpose
DCL: Data Control Language, and has the following directives:
GRANT gives privileges to the user
REVOKE takes privileges from the user
You can learn this language from the following references:
Learning SQL: Authored by: Alan Beaulieu
Head First SQL: Your Brain on SQL: Written by: Lynn Beighley
Database components
Databases consist of four main components:
data
hardware
programs
users
Database installation
Databases have special combinations, including: Relational structures, which depend on specific and specific elements of the different data elements, such as the value of an element dependent on mathematical operations that take place on other elements. The second structure is the structural structure, and this structure depends on the organizational relationship between the data elements. The third structure is the structure known as the hierarchical structure, and this structure is the one that depends on the existence of hierarchical relationships between the different elements. For example, several different data elements can fall under a single data element
Duties and functions of the database administrator
The DBA (Database Administrator) is considered the most important person working in the database department in any work environment such as companies or banks, because he is responsible for distributing all tasks and functions to the rest of the team members responsible for them, and he is also primarily responsible for the performance and readiness of databases, and data integrity And easy access to it by programmers or users, so he must be very familiar with how databases work, and he has the experience that qualifies him for this sensitive position, in addition to his work in securing databases and protecting them from electronic intrusions that may be exposed to them, and he must He must have good communication skills with others in order to ensure excellent results in a comfortable atmosphere within the team.
The work of the database administrator is usually in the location of the database itself, as he does not need to work in another place, and he is responsible for giving powers to programmers and users to access, modify and monitor the database. There are many certificates that allow holders to hold the position of database administrator, such as: MySql, Oracle Database Administrators, and Microsoft Certified Database Administrators (MCDBA)
