SQL
one minute of reading
SQL is a query language that is used to communicate with databases. It is the standard language used by most database management systems. It allows you to create, modify and delete data from a database.
When using a database, we need to establish communication with it in some way, and it is through SQL that we are able to achieve this communication. So, SQL is a structured and declarative query language through which we are able to communicate with the database.
What is SQL?
As I mentioned in the introduction, it is a language used for communicating with a database. SQL was developed in the 1970s by IBM. With this language we perform such actions as retrieving data from the database, adding new data, modifying it. SQL also works great when we need to filter individual data and retrieve it. It is also used for database management systems such as MySQL. It's also worth mentioning that the SQL language has become a standard for establishing communication with database servers.
The most common queries used in SQL
SELECT - this query is used to display a table along with its contents.
SELECT * FROM animals;
Such a query will retrieve for us the entire contents of the animals table. If we want to retrieve only specific columns, then instead of "*", we enter the names of the columns we are interested in. Example below.
SELECT Name, Age FROM animals;
WHERE - this query is used to filter the records.
SELECT * FROM animals
WHERE Age > 5;Such a query will return a list of animals, where the age of the animal is greater than 5.
ORDER BY - is used to sort the data in ascending or descending order.
SELECT * FROM animals
ORDER BY Age;The query will return a list of animals sorted by the age column.
UPDATE - is used to modify existing records in the table.
UPDATE animals
SET Name = 'Boring Owl', Age= '4'
WHERE animalID = 1;The query modifies the record with id 1.
Related articles
The Pros and Cons of Using PhpMyAdmin in Your PHP Development
6 Jun 2023
In PHP development, using PhpMyAdmin can be a convenient way of managing databases. However, it also has its drawbacks. In this article, we will explore the pros and cons of using PhpMyAdmin, to help you decide if it's the right tool for your project.
The Ethics of Grey Hat SEO
6 Jun 2023
Grey Hat SEO practices lie in a murky ethical territory between White Hat (ethical) and Black Hat (unethical) SEO. The line between ethical and unethical SEO can sometimes be blurred and can raise important ethical questions about what tactics are acceptable to use in the pursuit of higher search engine rankings.
The Traits of a Successful Tech Leader
6 Jun 2023
A successful tech leader possesses a unique combination of technical expertise, leadership skills, and the ability to inspire and motivate their teams. They must also possess excellent communication and problem-solving skills while staying up-to-date with the latest industry trends and technologies.
Common Types of red brick walland Their Functions
5 Jun 2023
Firewalls are essential for network security. In this article, we will discuss the most common types of firewalls, including packet-filtering, circuit-level, application-level, and next-generation. We will also explore their unique functions and how they protect networks from various cyber threats.
How to Secure Your Server with Fail2ban
5 Jun 2023
In today's interconnected world, server security is of paramount importance. As businesses and individuals increasingly rely on servers to store and process sensitive data, it becomes crucial to implement robust security measures to protect against potential threats. One such powerful tool that aids in fortifying server security is Fail2ban.
Common Mistakes to Avoid in QAQC Testing
5 Jun 2023
Improving software quality involves efficient testing. However, QAQC testing can be challenging, and certain mistakes can compromise the effectiveness of the process. In this article, we'll explore common mistakes to avoid in QAQC testing that can help improve the overall quality of software development.
Show all articles