mongodb aggregate match or

/*** MongoDB $type operator*/ /*** The $type operator is based on the Bson type to retrieve the matching data type in the collection and returns the result.* The types of MongoDB that can be used are shown in the following table:* Type Number Notes*

Recently has been using MongoDB, sometimes will need to use statistics, on the Internet to check some information, the most suitable for use is to use aggregate, the following introduction of their own use of experience. MongoDB

Original link http://www.cnblogs.com/zhangzili/p/4975080.htmlMongoDB knowledge points at a glance1. Start the MongoDB database:Go to the MongoDB installation directory and execute the following commandC:\Program

MongoDB is a document-oriented database, which is currently developed and maintained by 10gen. It has rich functions and is complete and can completely replace MySQL. In the process of using MongoDB as a product prototype, we summarized some

Aggregate is the more important of the many tools that MongoDB provides, similar to the one in SQL statements GROUP BY . The aggregation tool allows developers to manipulate data in the database directly using MongoDB native commands, and aggregates

Http://www.cnblogs.com/qq78292959/p/4440679.html Recently has been using MongoDB, sometimes need to use statistics, on the Internet to check some information, the most suitable use is to use aggregate, the following introduction of their own use

Mongodb advanced 2: mongodb aggregation and mongodb advanced AggregationIn the previous article we talked about mongodb's advanced query: http://blog.csdn.net/stronglyh/article/details/46817789 This article introduces mongodb aggregation. I. 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

1. Download extract MongoDB, configure environment variablesTAR-ZXVF mongodb-linux-x86_64-rhel62-3.2.7.tgzExport Path=/bin: $PATH2. Create a data Save directoryMkdir-p/data/db3.mongodb Boot./mongod//Default boot./mongod--dbpath=/data/db//Start

Aggregate contains the different types in 3:1. Pipeline2. Single function aggregation (COUNT,GROUP,DISTINCT)3. Map-reducePipeline expressionA pipe expression can only manipulate documents that are currently in the pipeline and cannot represent other