MongoDB

modifying primary shards Db.runcommand ({"Moveprimary": "DB", To: "Shard ID"});2. Merging data blocks (data blocks need to be empty)Db.runcommand ({"Mergechunks": "Db.collection", Bounds:[min_shardkey,max_shardkey]})3. Get Data block

Website address: https://www.mongodb.org/MongoDB is a 32-bit with 64 bits written in C + + due to the limitations of the operating system 32-bit maximum support for 2GB 64-bit unrestricted.I use the operating system is CentOS 6.5 on the official

Additional OverheadEach index occupies a certain amount of storage space, and the indexes need to be manipulated when inserting, updating, and deleting operations. Therefore, if you seldom read the collection, we recommend that you do not use the

The official MongoDB documentation shows that the overwrite query is the following query: All query fields are part of the index All the query return fields are in the same index Because all fields that appear in the query are part

You can use Db.copydatabase to back up the method of copying data.1.db.copydatabase ("from", "to", "127.0.0.1:16161"), copy a new to database. This is already the smallest data footprint. The data file of the to is generated in the database

Readpreference settings are involved in the replica set replica set, by default, both read and write are distributed primary node execution, but for less read, we want to read and write separate to share the pressure, So I want to use the secondary

Backup data:Mongodump-h 192.168.2.20-u game-p 12345678-d dbname-o/data/test/--excludecollection=user_statsWhere-H is the IP address,-u account,-p password,-d database name,-o path to store data,--excludecollection represents the collection to be

1. Additional Costs:Each index occupies a certain amount of storage space, and the indexes need to be manipulated when inserting, updating, and deleting operations. Therefore, if you seldom read the collection, we recommend that you do not use the

First acquaintance Mongodbby Sun Quan · August 8, 2014 to the new company, did not expect the company useful MONGO database, which let never contact MongoDB I am a little unprepared, can only be a bad supplement. In 2010, NoSQL set off a craze in

1.mongodb IntroductionMongoDB (named from "Humongous") is a scalable, high-performance, open-source, schema-free, document-oriented database. It is written using C + +. MongoDB Features:A. Collection-oriented storage: suitable for storing objects

To install MongoDB self-search, I offer here a GUI version similar to Navicat.1. Database levelShow DBS #查看服务器上的数据库 [local 0.000GB]Use test #切换到指定数据库 if test does not exist in the database, the test database will be createdDB #查看当前数据库

#more/opt/mongodb3.0/mongodb_im_conf_47020/mongodb3.0_im_47020.cnfDBPath =/opt/mongodb3.0/mongodb_im_data_47020/# Specify the database pathLogPath =/opt/mongodb3.0/mongodb_im_log_47020/mongodb.log # log pathLogappend = true # writes the log in an

Recently wanted to try Intel's WebRTC-based collaborative communications Development Kit, where the CS_WEBRTC_CONFERENCE_SERVER_MCU relies on MongoDB.What is MongoDB?MongoDB is a database based on distributed file storage. Written by the C + +

MongoDB was last installed and configured under Mac, this time under Windows also try to install and configure MongoDB.1, first download MongoDB compression package, download and extract to D or e disk. As follows:2. Configure environment variables:

Bibliography http://baike.baidu.com/link?url=DVJuvrT4ssbM8V1pKcoRx5H1CwRRCynC6_ Ix6ywirr414opislflppuy9hrdo4g-fr5vl9afbsvamwagpvn8g_Book over + read blog (http://www.cnblogs.com/huangxincheng/category/355399.html) + DIY installed MongoDB wrote demo

http://www.ttlsa.com/mongodb/mongodb-sort-limit-skip-usage/1. Sort is used for sorting. Sort ({"Field": 1})2. Skip skips how many results3, limit each query returns the maximum number of results;The use of the project is relatively good;Record again;

MongoDB Master-slave replication is a master can be more from and can master the master-slave replication. Here is the implementation of a master one from an arbiter server using a database server by providing a different port.A Start a MongoDB

MongodbInsert DocumentIn this section we will show you how to insert data into a collection of MongoDB.The data structure of the document is basically the same as JSON.All data stored in the collection is in the Bson format.Bson is a binary form of

MongoDB version 3.2 (currently up-to-date), the demo is the Linux under the MongoDB authorization authenticationFirst logon does not start authorization (MONGO default does not

A Field Annotated with @Id (ORG.SPRINGFRAMEWORK.DATA.ANNOTATION.ID) is mapped to the ' _id ' field.A field without an annotation but named ' id ' would be mapped to the ' _id ' field.Need to include Maven dependenciesDependency>