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mongodb is a database based on distributed file storage. Written in C++ language. The aim is to provide a scalable and high performance data storage solution for WEB applications. MongoDB is a product between relational database and non-relational database, which has the most abundant functions and resembles relational database. Install MongoDB ...

review Review of Related Articles mongoDB Query Advancement--Aggregation Pipeline(1) ReviewmongoDB Query Advancement--Aggregation Pipeline(2) ReviewmongoDB Query Advancement--Aggregation Pipeline(3) Review Classification of pipeline operators Pipeline operators can be divided into three categories: Stage Operators Expression Operators Accumula ...

1. Create a database Create grammar: use DATABASE_NAME If the database does not exist, create the database, otherwise switch to the specified database. Create yyf_mongodb database, db displays the current database > use yyf_mongodb switched to db yyf_mongodb > db yyf_mongodb If you want to view all databases, you can use the s ...

meteor Can quickly build pc, mobile, desktop applications. The biggest advantage is that when the data of the database changes, it can be pushed to the front end in real time, which is very suitable for the application development of real-time display. In react,react-native applications, only the same meteor background can be used to push data ...

abstract In the previous article, we have analyzed the connection of relational database and the principle of connection pool. In the Mongo database also exists, we often see some netizens asking Mongo to connect to the database or not, how to close. Whether the built-in database connection pool is single-threaded or multi-thr ...

The purpose of this crawler is to crawl the attention of a microblog user and the basic information of fans, including user nickname, id, gender, location and the number of fans. Then the crawler saves the data in the MongoDB database, and finally regenerates several graphs to analyze the data we get.   I. Specific steps: The crawling site we s ...

First, the cmd command line opens the MongoDB connection, and use the test (self-changing libraries) library. View the data created in the previous article in the owner table. Here is a json data structure for test data. var owner1 = { name: "Zhang San", age: 25, books: { name: "Tianya Mingyue Knife", author: "Gulong" }, favorites: { ...

MongoDB database 1.1 Introduction to NoSQL With the rise of Internet web2.0 website, traditional SQL database (relational database) has been unable to cope with web2.0 website, especially the super-large-scale and highly concurrent SNS (social network system, Renren) type web2.0 pure dynamic website, which has exposed many problems that are dif ...

－－－－－－－－－－－－－－－－－－－－－－－－－－－  Index creation, update and deletion in single mode －－－－－－－－－－－－－－－－－－－－－－－－－－－ －－－－－－－－－－－－－－－－－－－－－－－－－－－  Initialize Index Indexes can be initialized before they are created. For example, specify the number of shards and the number o ...

1. Target of this crawl To crawl data from websites and analyze and organize it, my goal is to completely recreate a webapp site for practice, so I'll think about how inputs are stored in MongoDB.The crawled data is temporarily stored in the json file first; of course, it can be stored directly in your own MonoDB, so the duplicated website is ...