digitalocean mongodb

Install and configure MongoDB in Linux1. MongoDB simple description A MongoDB is an open-source database system written in C ++ Based on Distributed File storage. It aims to provide scalable and high-performance data storage solutions for WEB applications. B MongoDB is a product between a relational database and a non-

MongoDB study NOTE 1: The download and installation of MongoDB are relatively idle over the past few days. I am going to learn about the MongoDB database. Today I have simply learned how to download and install MongoDB, and created a data warehouse that stores MongoDB. Share

In the previous article, we talked about MongoDB installation and management, which involves some concepts, data structures, and some API calls. It doesn't matter if you don't know it. It's actually very simple. This article will briefly introduce it. 1. Document is the core concept of MongoDB. Multiple key-value pairs are put together in an orderly manner. Document is the most basic data structure for

1), download MongoDB http://downloads.mongodb.org/win32/mongodb-win32-i386-2.4.5.zipDownload the Windows 32-bit version and unzip, the program files are in the bin directory, the other two directories are C + + calls are header files and library files. The bin directory contains the following programs: 1. Mongo.exe, command-line client tools. 2. Mongod.exe, database service program. 3. Mongodump.exe, datab

MongoDB database installation details (2). mongodb details How to change mongodb in java Java-based mongodb insert, read, modify, and delete operationsThis article describes how to operate MongoDB in Java and how to perform routine database operations in

Find () methodTo query the collection data from MongoDB, you need to use the MongoDB find () method.GrammarThe basic find () method syntax is as follows>db. Collection_name. Find() The Find () method displays all the files in an unstructured manner.Pretty () methodThe results are displayed in a formatted manner and can be used with the pretty () method.Grammar:>db. MyCol. Find(). Pretty() Exa

Tags: init ability B16 art needed tee boost trying check Once with MySQL database, all day is to write a large heap of SQL statements. To remember that these sqlkeyword are going to take a few days, write the eggs have exploded, when the contact with MongoDB, found not to write SQL, instantly think tall, instantly produced the impulse to learn to use it. 1.MongoDB Brief Introduction

1. Installing the MongoDb Driver package 2. Use the wrapper class: public class Mongodbwrapper:idisposable {private Mongoserver _server; Private Mongodatabase _db; Public Mongodbwrapper () {var uri = configurationsettings.appsettings["Mongourl"]; var url = new Mongourl (URI); var client = new Mongoclient (URL); _server = client. Getserver (); _db = _server. Getdatabase (URL. DatabaseName); }

This is a bit omitted in previous articles about using mongodb shell to execute scripts. Now I will add a supplement to this blog. I. Input a script file in the command line to define a javasciprt file, name: script1.js, content: print (iamalbert tshaointhescript1.js) defines another javascript file, name This is a bit omitted in previous articles about using mongodb shell to execute scripts. Now I will add

Mongodb deduplication, aggregation, query explanation, mongodb Aggregation I recently learned about mongodb and some people understand it: 1. deduplication Repeated template. getCollection (collectionName). distinct () returns the list set, which is the result after deduplication. 2. Aggregation Aggregation aggregation = Aggregation. newAggregation (Criteri

[MongoDB] interaction between arrays and range queries, mongodb array queries The scalar (non-array element) in the document must match each statement in the query condition. For example, if {"x": {"$ gt": 10, "$ lt": 20} is used for query, only documents with the "X" key value greater than or equal to 10 and less than or equal to 20 will be matched. However, if the x field of a document is an array, if an

Because the document structure of MongoDB is in the Bjson format (bjson full name: Binary JSON), and the Bjson format itself supports data in binary format, you can save the data in binary format of the file directly into the MongoDB document structure. However, because the maximum length of a bjson cannot exceed 4M, it limits the maximum number of files that can be deposited in a single document beyond 4M.

On the blog about MongoDB processing large file ideas and processes, let's look at how the Java driver to implement file operations. The Java driver provided by MongoDB encapsulates specific implementation details, and we are very simple to operate. Add, delete, and read files by using a few components: Gridfs: A core class that provides creation, discovery, and deletion of files. Gridfsdbfile: A file read

This is a bit missing from the previous article about running scripts with MongoDB's shell, which is now supplemented in this blog.One, passing in the script file on the command lineDefine a JAVASCIPRT file with the following name: Script1.js, for example:Print ("I am Albert Shao in the Script1.js")The definition also has a JavaScript file, named Script2, for example:Print ("I like to read and study")The following results are obtained for example in the command form:Note: The script file must be

Tags: MongoDB sparse uniqueCreate an index You can specify options, and indexes that are built with different options behave differently.First, unique indexA unique index ensures that each document has a unique value for the specified key. For example, to determine that the username key in a document is not duplicated, create a unique index:> Db.users.findOne () {"_id": ObjectId ("54ad5826245d1b7d58b53238"), "I": 2, "username": "User2", "Age": "Create