MongoDB

The MD5 is stored in the Fs.files metadata information after uploading, which is used to verify the MD5 value after the user gets the large file.The way to view MD5 values in Linux is: md5sum file nameSo let's look at the MD5 of the get file from

1. Backing up small shards of cluster data using MongodumpIf the dataset for a shard cluster is small, you can use Mongodump to connect to the MONGOs instance for data backup. By default, mongodump to non-primary nodes for data queries.Such

The emergence of each technology or product has its background, not figment or out of thin air, is to solve specific problems for a particular period of historical development. Let's take a look at what turned out to be a specific problem with

This paper mainly introduces the simulation of MONGO shards on a win7 computer . If you have more than one server, you can deploy each MONGO on a single computer. We will configure 3 MONGO shards, 3 configuration servers, and 1 routing servers.

Modify the Index.js as follows:varExpress = require (' Express ');varRouter =Express. Router ();varCrypto=require (' Crypto ');varUser=require (".. /models/user.js ");/*GET home page.*/Router.get (‘/‘,function(req, res, next) {Res.render (' Index ',

In web development, the session represents the "sessions" of the HTTP server and the client (for example, the browser), each client has its corresponding session saved on the server side, usually used to hold some information associated with the

The first two weeks of work is relatively simple, easy to fix, this week's work suddenly difficult to get up, the cost of a great effort to write, there are many needs to improve the place, at present can only be considered reluctantly realized the

MongoDB Common commands:Talk about a special situation, if the admin uses encryption, then you create a database must be encrypted to use, this is the problem I personally met.  Enter the MongoDB command line, note: The default entry is the test

Installing MongoDBMongoDB downloads the corresponding system version of the executable fileMy system environment: rhel-server-6.2-x86_64Unpack the Packagetar zxvf mongodb-linux-x86_64-rhel62-3.0.2.tgzYou can view the Readme in the directory to

Objective:My version is 2.6.9, has Auth's master and slave, found in the internet for a long time have not found, finally found in the official online method, in fact very simpleIf you do have a verified master-slave, then need to use the KeyFile

1. Download the corresponding package to the MONGODB website2. Unzip the tar zxvf Mongodb.taz3. Move the extracted folder to the directory you specifiedMV MongoDB./develop-tools4. Add the Mongod command to the environment variableVI

MongoDB Start Command mongod parameter descriptionThe main parameters of Mongod are:Basic Configuration-------------------------------------------------------------------------------- --quiet # quiet Output --port

MongoDB is used, but the operation return data calls the Find method to return the need to deal with, it is very uncomfortable, borrowed from the next commons-dbutils on the Java database operation, and also to MongoDB's return data implementation

Some conceptsFor MONGO in data disaster recovery, the recommended pattern is to use replica set mode, which has an external primary server primary, and N replica server secondary (n>=1, when n=1, need to have an arbiter server arbiter when n> 1

? I. master-slave replication • A. Primary server: ~/work/mongodb-osx-x86_64-2.6.2/bin/mongod--dbpath./db/--logpath./log--logappend--fork --port 27017--master--oplogsize=64 • B. from the server:./mongod--dbpath. /db/--logpath.

"Step by Step Spring+maven+mongodb" one: Environment configurationFirst, the development environmentEclipse (Java EE Edition)Second, the environment configuration 1.JDK configuration1.1.1 Download JDK:

Reference: http://wengzhijuan12.blog.163.com/blog/static/3622414520137104257376/http://wengzhijuan12.blog.163.com/blog/static/3622414520137104257376/http://blog.csdn.net/shmnh/article/details/41976451Replication of the upgraded version of

Data Center reconstruction-why do we need to separate the card table from the student table? During the reconstruction of the fee-based database in the IDC room, the previous Studetn_Info was divided into Card_Info and Student_Info. It is easy to

Data Structure-Hash FunctionHash search In the previous search algorithm, the time complexity is O (n) or O (2n). The efficiency depends on the number of "comparisons. Even if the search results of a table using the sort tree structure are different

About the NOZEROCONF = yes parameter in linux/etc/sysconfig/network About the NOZEROCONF = yes parameter in linux/etc/sysconfig/network Today, we saw this parameter in the CSSD Fails to Join the Cluster After Private Network Recovered if avahi