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Required software: vscode, official website link Download: https://code.visualstudio.com/ ； (you can also use the editor you are used to) node.js, official website link Download: http://nodejs.cn/ ； Mongodb, official website download link: https://www.mongodb.com/try/download/community , we can just install the community version. (mac users ...

CentOS7.2 64 bit installation of mongodb4 4.1 (detailed) Here, I use yum to install automatically. I strongly don't recommend Xiaobai to decompress the compressed package for automatic installation. There are too many pits! Introduction to environment variable path mongodb bin directory: / etcdbpath of mongodb: / var/lib/mongologpath of mong ...

1, Connect database 1. Connect database 2. View a list of all databases show dbs 2, Create database, view and delete database 1. Use database, create database use Database name If you really want to create this database successfully, you must insert a data. Data cannot be directly inserted into the database. Only data can be inser ...

pipeline operation symbol Help you carry out complex operations. Each symbol will accept documents and do corresponding operations on these documents, and then pass the results to the next pipeline until the final results appear. db.getCollection('sales').insertMany([ { "_id" : 1, "item" : "abc", "price" : 10, "quantity" : 2, "date" : ISODate ...

Official documents in English: https://docs.mongodb.com/manual/ MongoDB Chinese website: MongoDB Chinese website | MongoDB Chinese documents brief introduction MongoDB is a document database designed to facilitate application development and expansion. MongoDB is a document database designed for ease of application development an ...

This article was updated on January 8, 2022, using MongoDB 4.4.5. Create shards under a single server Ensure that the / data/db directory exists and that the current system user has read and write permissions. For example (permission needs to be set according to the actual situation): su root mkdir -p /data/db chmod 0777 /data /data/db St ...

In this article, you will see: Conceptual relationship among MySQL, SQL, ORM and serializeUse of sequenizeThe concept, usage, principle and difference of join table relation in sequenizeHow to optimize database query 1 Concept MySQL Most people know about MySQL and SQL. After all, it is written in textbooks. MySQL is a typical relational dat ...

Introduction - learn node The purpose of JS is to help you open the black box of the server. Only by understanding the server can we better cooperate with the server developers in collaborative development 1.1 review and reflection 1. Why can javaScript be executed in the browser? 2. Why can javaScript operate DOM and BOM 3. javaScript ...

mongodb index rule Mongodb's indexing rules are basically the same as those of traditional relational databases. Most techniques for optimizing MySQL/Oracle/SQLite indexes are also applicable to mongodb. Why index When some conditions are used in the query, the key can be indexed to improve the query speed.When the amount of data is lar ...

reference resources Python operates MongoDB. Just read this article 1. Install MongoDB windows download address of mongodb MongoDB provides precompiled binary packages. (1) Download msi file. After downloading, double-click the file and install it according to the operating instructions. During installation, you can set your installation dir ...