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What’s the Difference Between HAVING Clause and WHERE Clause in PostgreSQL?

In PostgreSQL, the WHERE clause filters the data of each row and then groups the data while the HAVING clause filters the grouped data.

PostgreSQL Cheat Sheet - Basic Commands

This blog presented a cheat sheet that assists us in working with the Postgres databases, schemas, tables, and users/roles, efficiently.

PostgreSQL Pattern Matching: LIKE VS NOT LIKE VS ILIKE

The LIKE operator matches the search expression with the specified pattern and retrieves true if the match is found. The NOT LIKE operator negates the results of the LIKE operator.

How to Connect PostgreSQL to Java Using JDBC

To connect PostgreSQL to Java via JDBC, integrate Postgres JDBC Driver with Java, and establish a new connection. After this, you can execute PostgreSQL Queries from Java.

PostgreSQL LENGTH() Function With Practical Examples

The Postgres LENGTH() function accepts a string as an argument and calculates the total number of characters in that particular string.

How to Show Databases in PostgreSQL

In PostgreSQL, the “\l” command and “pg_databases” catalog are used to show the list of databases. Use the “\l+” command to show databases with more details.

How to Create a Database in PostgreSQL

A Postgres database can be created using “CREATE DATABASE” or “createdb” commands. The difference is that the “createdb” can be executed from the command prompt.

How to Install PostgreSQL (psql) on Arch Linux

To install PostgreSQL on the Arch system, use the default Pacman package manager tool. More specifically, using the “sudo pacman -S postgresql” command.

How to Use LIMIT Clause in PostgreSQL

In PostgreSQL, the LIMIT clause and OFFSET clause allow us to retrieve only a subset of data returned/generated by the SELECT query.

How to Install PostgreSQL on Ubuntu 24.04

To install Postgres on Ubuntu 24.04, first update the system packages and then use the “sudo apt install postgresql postgresql-contrib -y” command.