SQL (Structured Query Language) is a powerful tool used for creating, manipulating and retrieving data from databases. While working with these databases, there are many instances where we have to combine data from one or more tables. This can be easily done using the JOIN operation. The SELF JOIN is a type of JOIN that …
While working with databases in SQL (Structured Query Language), we may have multiple tables in a single database. In instances where we have to retrieve data from multiple tables and combine them, the JOIN operation comes into play. In this article, we’ll explore the OUTER JOIN operation, a specific type of JOIN operation that combines …
SQL Outer Join: LEFT, RIGHT & FULL With Examples Read More »
In this tutorial, we will be learning about the TRUNCATE TABLE statement in PostgreSQL which is used to delete records from the table. Many new folks misunderstand the TRUNCATE TABLE with the DROP TABLE statement. We will clear all your misunderstandings in this tutorial. So, be with us and let’s get started! PostgreSQL TRUNCATE TABLE …
PostgreSQL TRUNCATE TABLE: Syntax, Examples & Limitations Read More »
In this tutorial, we will learn about the WHERE clause in PostgreSQL. Though it is a very simple topic, it is recommended to understand how the WHERE clause works in order to produce the required output. Therefore, we will also learn some important things about the WHERE clause. So, let’s get started! Introduction to PostgreSQL …
PostgreSQL WHERE Clause: Introduction, Syntax & Examples Read More »
In this tutorial, we will be learning about the DROP TABLE statement in PostgreSQL which is used to remove the existing table from the database. Apart from just deleting the table, we will learn some additional things as well. So, let’s get started! PostgreSQL DROP TABLE Statement The DROP TABLE is a DDL command which …
PostgreSQL DROP TABLE: Deleting Tables from Database Read More »
In this tutorial, we will learn to create a sequence in PostgreSQL. This topic might seem a little bit confusing but trust me, it is as simple as creating a table. So, without getting distracted from the topic, let’s dive straight into it. Introduction to PostgreSQL Sequence A sequence is simply an object that generates …
PostgreSQL CREATE SEQUENCE: Introduction, Syntax & Examples Read More »
In this tutorial, we will learn how we can change or modify the column data type or change the size of the data type in PostgreSQL. Along with the syntax and examples, we will learn the pros and cons of it. So, let’s get started! Introduction Creating a database and tables is the backbone of …
In this tutorial, we will learn to delete a column from the table using the ALTER TABLE statement with the DROP COLUMN keyword. We can remove one or more columns using this statement. So, let’s see how is it done! Introduction to PostgreSQL DROP COLUMN In PostgreSQL, the DROP COLUMN clause is used with the …
PostgreSQL DROP COLUMN: Remove Columns From Table Read More »
For new SQL developers, especially at the beginning, knowing what faults to look for is crucial. When you write a query, an error message appears instead of the expected output. Don’t Worry it’s completely normal! Any computer language, including SQL, is prone to coding errors. New programmers frequently make more errors and spend a long …
Five Common SQL Mistakes to Avoid: A Beginner’s Guide Read More »
In this tutorial, we will learn how can we rename the table using the RENAME command. We have to use the RENAME keyword with the ALTER TABLE statement to make it work. So, let’s see how it is done! PostgreSQL RENAME Table Statement First of all, the RENAME keyword cannot be used standalone to rename …
Renaming Tables in PostgreSQL: A Step-by-Step Guide Read More »