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Sometimes, you have to select first N rows of MySQL database according to your project requirements. n The value of varies according to the requirement; it can be TOP 1 row or TOP 30 rows. We will learn how to select top N rows using the cl...

In this article, we will learn how to terminate a PostgreSQL session. Any open connections are run by background processes or tasks, PSQL which may no longer exist despite exiting the user interface or command line tool. Use ps -ef or grep...

In this article, we will discuss the issue of deleting a collection in MongoDB in detail and explain the different methods and queries used to delete a collection in MongoDB. MongoDB delete collection There are two ways to delete a collecti...

This post will discuss how to quickly and easily import all three file formats (JSON, CSV, and TSV) into your MongoDB database instance. So without further ado, let’s get started. What is MongoDB MongoDB is a NoSQL (non-relational) databa...

In this article, we briefly discussed about inserting records in MongoDB collection. We also explained different ways to insert these records. In addition, Upsert and $setOninsert are briefly introduced. Upsert in MongoDB Upsert is a MongoD...

Python is the most popular programming language for data science, and MongoDB, with its flexible and dynamic schema, is a great combination for creating modern web applications, JSON APIs, and data processors, to name a few. MongoDB also in...

This post will show you how to add elements to an array in MongoDB using various techniques. Pushing or appending elements to an array is very convenient for quickly appending lists by adding or moving objects in an existing MongoDB documen...

IN Today, we will take a closer look at how the and ANY operators work in PostgreSQL . However, remember that both are standard SQL operators, which means we can use them on multiple management platforms. By looking at them one by one and t...

Last time, we read about how to use it in PostgreSQL UPSERT . In a quick review, UPSERT is short for , which tends to insert values ​​into the table INSERT ON DUPLICATE UPDATE if they don't match a previous entry . If they do, they are...

ON DELETE CASCADE Before we start looking at different solutions for implementing in PostgreSQL , we will first understand ON DELETE CASCADE what is and what it does. Let's assume you have two tables, one of which inherits from a parent tab...

In our article, we mainly work on the PostgreSQL application called pgAdmin [app. number] , which can be downloaded from the PostgreSQL website. Therefore, we hope that you already have the application installed or another alternative where...

USERNAME Many PostgreSQL users may be asked for their database settings for the first time when logging in PASSWORD . However, just learning these settings is not all you need to know. What is the server in Rails 4? The server in Rails 4 us...

PSQL is a terminal-based front-end for the PostgreSQL database server. It uses either command-line arguments from an input file or from the command line, and is portable and easy to use. It also helps in writing scripts and letting other ta...

Before we start looking at different solutions to this problem, let's understand what a CSV file is and how output works in PL/pgSQL. PL/pgSQL output is the data displayed after running certain types of queries in PostgreSQL. Sometimes, as...

Let's start with a simple question. INFORMATION_SCHEMA What exactly is it? INFORMATION_SCHEMA Provides us with information about the objects defined in our database. It contains a set VIEWS of objects that store QUERY the database objects....