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This article will introduce the findOneAndUpdate() method in MongoDB. We will use this method to update the first matching and embedded document. Using findOneAndUpdate() method in MongoDB db.collection.findOneAndUpdate() Method updates the...

Sometimes, we need to find a document by comparing two fields. For example, we may need to consider both the sequence number and the ID number when selecting documents in a MongoDB collection; we will see this later in this tutorial. In thi...

This article is dedicated to helping you use the mongoimport command, which allows users to import CSV files into a database in MongoDB. This article explains what a CSV file is. An example CSV file is provided at the beginning to help you...

This article discusses in detail about exporting a collection to CSV format in MongoDB. We have two methods to export a collection to CSV format: Studio 3T and MongoExport. Export a collection to CSV format in MongoDB using the Studio 3T Ex...

Sometimes we need to create an index that contains multiple fields. For example, if your document contains a field called Sex, it may contain two other fields, such as Male and Female. These fields may have values ​​like Yes or No. In t...

In MongoDB, it is not mandatory for all documents to contain the same fields. Now, if you want to get all the documents in a MongoDB collection that contain only a specific field, then you may need to specify a common field as an index. Thi...

In this article, you'll learn about unique indexes, including what they are and how to create them in MongoDB. Additionally, the process of making a user's email unique in MongoDB is briefly described. The contents of this article are as fo...

In database management systems, locking mechanisms ensure the consistency of the entire result. For example, if some writing process is in progress on the data, a read command cannot be executed at the same time. Database resources are lock...

In this article, the problem of finding objects between two dates was briefly discussed. In addition, the operators $gte, $lte, $gt, and $lt used for this purpose were briefly explained in detail. Querying date ranges in MongoDB This sectio...

This MongoDB tutorial discusses the issue of returning Date-based queries. In addition, there is also a good tutorial on how to use Date Range queries in MongoDB. Using date ranges in MongoDB We will learn to write MongoDB date range querie...

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...

This article shows how to change a column type to another data type in Postgres. ALTER TABLE To change the column type in Postgres, use the command ALTER TABLE table_name ALTER COLUMN column_name [ SET DATA ] TYPE new_type ; Use 表名 , , 列...

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...

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,...

Today, we will learn how to find a value in a PostgreSQL string and select it if it matches certain conditions. Suppose you have a string carabc and want to see if it contains a value car . Therefore, you will try to use a function that tel...