Tiempo de lectura: 2 minutos In SQL, joins are used to combine rows from two or more tables based on a related condition between them. I will show you how to use the most important joins: INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN, with NULL checks to handle unmatched rows. 1. INNER JOIN INNER JOIN returns only the … Read more
Tiempo de lectura: 2 minutos In SQL, joins are used to combine rows from two or more tables based on a related condition between them. There are several types of joins, but the most important ones are: INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN. Next, I’ll show you how to use each one with examples. 1. INNER JOIN … Read more
Tiempo de lectura: 2 minutos Good morning! And happy holidays! 🎄 Today I bring you a basic tutorial about HTTP status codes. It’s always good to have them handy, so here are the most common ones! Common HTTP status codes: 200 OK: The request has been successfully processed. 400 Bad Request: Error in the client’s request. It could be due … Read more
Tiempo de lectura: 2 minutos Reading time: 2 minutes MariaDB is an open-source relational database management system that was released in 2009. It was created as a fork of MySQL by its original creator, Michael Widenius, after MySQL was acquired by Oracle Corporation in 2008. Michael Widenius decided to create MariaDB due to his concerns about the future of MySQL … Read more
Tiempo de lectura: < 1 minuto Reading time: < 1 minute In SQL, a null value is a value that does not have a specific or valid value. In other words, a null value represents the absence of a value in a specific column. It is important to note that a null value is different from a zero value or an ... Read more
Tiempo de lectura: 2 minutos Reading Time: 2 minutes Good afternoon, friends! Today, I’m going to talk to you about the SQL keyword ORDER BY. Are you ready? Let’s get started. SQL is a programming language used to work with databases. The “ORDER BY” command is used to sort the results of a query in ascending or descending order based … Read more
Tiempo de lectura: 2 minutos Reading Time: 2 minutes Good afternoon! We continue with tutorials on SQL The SQL operators AND, OR, and NOT are used to combine multiple conditions in a WHERE clause. Each has a specific function and is used in different situations. The SQL AND operator is used to combine two or more conditions in a WHERE … Read more
Tiempo de lectura: 2 minutos Reading time: 2 minutes Good morning, let’s continue with SQL The SQL WHERE clause is used to filter the results of a database query. It allows you to use various operators and functions to specify filtering conditions. For example, if we want to select all customers from a table who are older than 30 years, … Read more
Tiempo de lectura: < 1 minuto Reading Time: < 1 minutes Good afternoon everyone, Today, we continue with SQL tutorials, and we will explain the SQL SELECT DISTINCT statement with examples. SQL SELECT DISTINCT is a clause used in SQL to select only the unique values from a column or set of columns in a table. It is very useful when we ... Read more
Tiempo de lectura: < 1 minuto Reading time: < 1 minute Good afternoon, The SELECT statement is one of the most commonly used statements in SQL and allows us to retrieve data from a database. The basic syntax of the SELECT statement is as follows: SELECT field1, field2, ... FROM table WHERE condition The SELECT clause specifies which fields we want ... Read more
