distinct in mongodb

A brief introduction to 1.1 MongoDBIn today's database market, MySQL is undoubtedly a place to occupy. As an open-source relational database , MySQL is widely used in the background of major web sites, and assumes the important role of information

If you have never been familiar with MongoDB or have a little understanding of MongoDB, if you are a C # developer, take a few minutes to read this article. This article will take you step by step to get started easily. Read directory 1:

A brief introduction to 1.1 MongoDBIn today's database market, MySQL is undoubtedly a place to occupy. As an open-source relational database , MySQL is widely used in the background of major web sites, and assumes the important role of information

In the mapreduce> of data aggregation in the previous article There are three basic aggregation functions in MongoDB: count, distinct, and group. Let's take a look at these three basic aggregate functions separately.(1) CountRole: The number of

Http://www.cnblogs.com/yoolonet/archive/2011/08/27/2155701.html A series of articles about MongoDB recently used MongoDB as a data storage system to record their own applications and problems in actual development. I hope this will be helpful to my

Comparison table of operations between MongoDB and MySQL and comparison table of mongodb Comparison tables and differences between MongoDB and MySQL MySQL and MongoDB are both open-source common databases, but MySQL is a traditional relational

Install MongoDB 3.0 server on CentOS71. Download and install MongoDB 3.0 official version released! This marks a new development stage for MongoDB databases, providing a powerful, flexible, and easy-to-manage database management system. MongoDB

0) MONGO: Connect MongoDB database via client1) Show DBS---Display the currently created database2) Use test---Create or switch databases3) Db.dropdatabase ()--Delete the current database3) Show Collections: Displays the collection created by the

http://www.mongodb.org/Agile and scalableMongoDB (from "HuMongoUs") was an Open-source document database, and the leading NoSQL database. Written in C + +, MongoDB features: Document-oriented storage»Json-style documents with the dynamic schemas

This article introduced the MongoDB in the MapReduce implementation of data aggregation method, we mentioned MongoDB in the data aggregation operation of a way--mapreduce, but in most of the day-to-day use of the process, We do not need to use