Tag Archives: sql

In this article, we will explain the differences between SQL vs NoSQL Databases. 1. Introduction We will check the relational (SQL) and non-relational (NoSQL) data structures. While both are viable options, there are key differences between the two that users must keep in mind when making a decision. 2. Differences between SQL and NoSQL 2.1 Database Architecture At the most ...

Hello. In this tutorial, we will learn and understand what SQL is and how does it work. 1. Introduction SQL stands for Structured Query Language and is used to extract and organize data stored in relational databases like MySQL, PostgreSQL, Oracle, etc. A relational database consists of rows and columns that allow fetching specific information from databases that can be ...

In this article, we will make an introduction to SQL Basics. 1. Introduction Structured Query Language (SQL) is a standardized database language that is used to create, maintain, and retrieve data from a relational database. SQL was initially developed at IBM San Jose Research Laboratory in early 1970. IBM released the first Relational Database Management System (RDBMS) – Multics_Relational_Data_Store in June ...

In this article, we will explain the SQL SELECT DISTINCT Statement. 1. Introduction The SQL DISTINCT keyword is used to eliminate the duplicate records and return only unique records. Here is the SELECT DISTINCT syntax: SELECT DISTINCT {column1}, {column2}, ... FROM {table_name} [WHERE {condition}] 2. Technologies Used The example code in this article was built and run using: MySQLDocker 3. ...

In this article, we’re going to see how to test null values in an SQL database. 1. What is a NULL Value? Basically, a field with a NULL value in a SQL table is a field without value. When creating a table, we can mark a column that accepts null values when inserting data into the table. A null value ...

In this article, we will discuss the COUNT function in SQL, different ways of using it, and how to combine it with other keywords like GROUP BY and HAVING. 1. Introduction Many times, the information we want from a database table is not available in a single row but in a group of rows or in the result of a ...

In this article, we will discuss JOINs in SQL (Structured Query Language), various types of JOINs, and their syntax. We will also run SELECT queries using different types of JOINs on data in sample tables and view the result sets. You can also check this tutorial in the following video: SQL Join Tutorial – video 1. Introduction In real-world applications, ...

Hello in this tutorial, we will understand how to create a RESTful API in a Node.js environment running on an Express.js server and using a PostgreSQL database. The tutorial will cover the CRUD operations on the API which will execute the corresponding database commands. 1. Introduction RESTful API stands for the standard web service interface used by the applications to ...

Hello in this tutorial, we will understand how to create a RESTful API in a Node.js environment running on an Express.js server and using a MySQL database. The tutorial will cover the CRUD operations on the API which will execute the corresponding database commands. 1. Introduction RESTful API stands for the standard web service interface used by the applications to ...

In this example, we will see how to use the BETWEEN operator included in the SQL. 1. Introduction The BETWEEN is a logical operator, often used in the WHERE clause of the SELECT, UPDATE, and DELETE statements, and gives us the ability to specify whether a value is in a given range or not. Syntax SELECT column_name(s) FROM table_name WHERE column_name ...