PostgreSQL tutorials with examples: install PostgreSQL, write SELECT queries and joins, work with dates, run VACUUM, back up data and use PL/pgSQL.
In this PostgreSQL tutorial, we will learn about PostgreSQL Joins. Here we will learn how to use joins in PostgreSQL and PostgreSQL Joins Types. PostgreSQL Joins PostgreSQL joins are used to merge columns from one (self-join) or more tables based on the values of the common columns between related tables. The standard columns are generally the … Read more >>
As a database consultant, I’ve encountered many developers confused about timestamp functions in PostgreSQL. One question that repeatedly comes up is: “What is the difference between current_timestamp and now() in PostgreSQL” PostgreSQL current_timestamp vs now Let’s start with the short answer: current_timestamp and now(). They are functionally equivalent in PostgreSQL. They both return the current … Read more >>
In this PostgreSQL tutorial, I show you how to use PostgreSQL current_timestamp to get the current timestamp of the system. Also, I will show you the way to control the format and convert the timestamp value returned by the CURRENT_TIMESTAMP to the UTC time zone. PostgreSQL current_timestamp PostgreSQL has the function current_timestamp to get time … Read more >>
In this PostgreSQL tutorial, we will learn how to connect to a PostgreSQL database in Linux. If you’re using Linux as an operating system and have PostgreSQL installed, this step-by-step tutorial will take you through the process of connecting to a PostgreSQL database. How To Connect PostgreSQL Database In Linux To connect PostgreSQL database in Linux, follow … Read more >>
In this PostgreSQL tutorial, I will show you how to use the PostgreSQL Average Count to compute the average value of the given set of values or columns. You will learn how to use the AVG() function with the HAVING, GROUP BY clause, and the DISTINCT operator. Additionally, you will understand how to deal with null values while computing the … Read more >>
In this PostgreSQL tutorial, I will show you how to rename column in PostgreSQL, where you will understand how to check the column’s existence in the table before renaming the column. How to Rename Column in PostgreSQL Sometimes, as business requirements change, you also need to rename the columns, and there can be different reasons … Read more >>
I’ve created hundreds of database users across various environments while working with PostgreSQL. In this comprehensive guide, I’ll walk you through everything you need to know about how to create a user in PostgreSQL. How to create user in PostgreSQL Let’s discuss each approach individually. Approach-1 Creating Users via GUI Tools To create user in … Read more >>
As a database developer, I recently got the opportunity to work with PostgreSQL Update Limit. In this PostgreSQL tutorial, I am going to show you how to use Postgres Update Limit. You will understand how to update a certain number of records or rows of the table using the keyword ‘LIMIT’ with the ‘UPDATE’ statement. … Read more >>
In this PostgreSQL tutorial, I will teach you how to use the Postgres Rank Function to assign a rank value to rows of the tables in a specific order with multiple examples. PostgreSQL RANK Function The RANK() function in PostgreSQL is a window function that assigns a number, known as a rank, to each row of the result set … Read more >>
Recently, I was required to export data to CSV format in PostgreSQL. In this tutorial, you will learn how to use Postgres Export to CSV. Basically, in this tutorial, you will gain the knowledge of exporting the PostgreSQL table data to the CSV file. Postgres Export to CSV Suppose you have a database with multiple … Read more >>
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