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In this article, we will address how to use the MongoDB distinct() method to return unique values. In addition, returning unique values ​​in arrays and fields is discussed. In MongoDB, sometimes you may want to present or return unique

A CSV file is .csv a text file with a .CSV extension and the contents are separated by commas. This file can achieve different goals, such as loading data into database tables and importing data into Google and Excel spreadsheets. When work

Today we will learn how to add constraints after the rows in a table have been created UNIQUE . The UNIQUE constraint guarantees that the data in a row is unique in that column. So if the column ID exists, all rows will have unique values,

if Statement evaluates a condition by returning true or false value. We can use it to perform condition based queries. This article will teach you how to write if conditional statements and understand how conditional statements can help you

This article will explain how to delete a user from a MongoDB database. In addition, we will see an example to make the topic easier to understand. Deleting a User from a MongoDB Database Sometimes we need to remove a particular user from t

This article discusses how to import SQL files in PostgreSQL. psql Import SQL files in PostgreSQL using command To import the SQL file, run the following command: psql - U dbuser - h localhost databasename filename. sql If the file is locat

Today, we will learn how to kill or stop a running query in the background when working with PostgreSQL database. This may happen if the frontend stops working but a background process is still running. In this case, you may want to kill th

When working with projects where you need to validate the size of an array or find elements whose size is greater or less than a certain length, you might use MongoDB operators such as $size, $where, $exists, etc. The methods discussed belo

This article will discuss how the $unset operator works in MongoDB. Additionally, we will demonstrate the use of this operator to remove a field from all documents in a MongoDB collection. $unset operator in MongoDB $unset is an operator us

This article shows how to check the version of Postgres. Checking Postgres Version in Windows C: \ Users \ Admin psql -- version psql ( PostgreSQL ) 14.0 C : \ Users \ Admin postgres -- version postgres ( PostgreSQL ) 14.0 The version shown

This article will discuss creating schemas in PostgreSQL using SQL queries or psql. CREATE SCHEMA Use the statement to create a pattern in SQL query To create a new schema, execute the following command. CREATE SCHEMA test_schema To view al

This article will discuss the timestamp types in PostgreSQL and show how they differ. Timestamps in PostgreSQL In PostgreSQL, there are two types of timestamps. Timestamp without time zone Timestamp with time zone The first stores the local

Sometimes we need to delete data from a database based on specified criteria. Unlike other SQL databases, MongoDB does not include SQL queries for this purpose. Instead, it uses commands. This article will discuss how to delete documents ba

Data backup is a critical process to ensure that preventive measures are effective in the event of an incident such as data loss. We can back up data in different forms and ways depending on the size and environment. This article will discu

PostgreSQL , also known as Postgres, is a leading object-relational database system. It is popular because it is highly compliant with the SQL standard and includes additional features that simplify processing complex data sets at scale. Po

In this article, case insensitive queries are discussed briefly and in detail. Also, case insensitive search queries are explained in detail. This article discusses the following topics. Case-insensitive search Improve case-insensitive regu

This short article will cover the various ways to use Compass filters in MongoDB . Compass Filters in MongoDB MongoDB has a GUI called Compass . It is also known as MongoDB GUI. Users can use MongoDB to inspect the contents of their stored

This article will discuss different types of ranges to compare dates in PostgreSQL. Date ranges in PostgreSQL By default, PostgreSQL provides some ranges to compare values. In particular, we can use daterange and between to compare dates. T

In this article, we will change the user password in Postgres. Changing User Passwords in Postgres Using Windows Open from the menu or search bar SQL Shell (psql) . Connect to the default database using the default port. If you set it up wi

数据库连接 A string is an expression in which there are all the parameters necessary to establish a connection from a terminal device to a database. It contains databases 用户名 , 密码 , 名称 , 主机地址 and 端口 . This con