Mongodb basic operations

1. Installation: Take my local machine as an example:

1) command installation method:

1.1 decompress the downloaded package to D: \ Installed \ MongoDB.

1.2 open the command prompt as an administrator and switch the directory to the D: \ Installed \ MongoDB \ bin directory (you can also set the environment variable so that you do not need to switch the directory ).

1.3 run the following command

Mongod -- dbpath D: \ Installed \ MongoDB \ data \ db -- logpath D: \ Installed \ MongoDB \ log \ mylog. log -- install -- serviceName "MongoDB"

After the installation is complete, enter the following URL in the browser: http: // localhost: 27017/. If the following content appears, the installation is successful:

You are trying to access MongoDB on the native driver port. For http diagnostic access, add 1000 to the port number

Command explanation: -- dbpath: storage location of mongodb database files; -- logpath: Location of mongodb log files -- service name of serviceName mongodb

 

2) Configuration File Installation (recommended)

2.1 create a configuration file named mongod. cfg (the name is not mandatory) and place it under D: \ Installed \ MongoDB (the location is not mandatory). Write the following content to the configuration file:

Dbpath = D: \ Installed \ MongoDB \ data \ db

Logpath = D: \ Installed \ MongoDB \ log \ mongod. log

The content is the configuration information during mongodb installation.

2.2 enter the command prompt as an administrator and run the following command:

Mongod -- config d: \ mongodb \ mongod. cfg -- install

After the installation is successful, the service name defaults to MongoDB.

 

==================================================== Common commands and indexes of mongodb operation

Common commands: ==== view the current database status db. stats () === the personalized system can help Mark slow queries. The command to enable it is as follows: db. setProfilingLevel (1) = view personalized data, and output all the log databases whose query time exceeds Ms. system. profile. find ({millis :{$ gt: 100 }}) = view copy information rs. status () === view lock status use configdb. locks. find () ========= Database Backup steps: 1. Write the data in the cache to the disk, lock the database, and prohibit writing data to the database. fsynclock () 2. Create snapshot 3. Unlock the database. fsyncUnlock () ======= create an index ensureIndex () = Example 1: {"field1": 1 }{ "field2, field3": 1 }{ "field2 ": 1, "field3": 1} indexes can also be created on sub-documents, such as db. factorie S. find ({metro: {city: "New York", state: "NY" }}) = Example 2: people class: {"_ id": ObjectId (), "name": "john smith", "address": {"street": "Main", "zipcode": 100081, "state ": "WI"} index creation statement: db. people. ensureIndex ("address.zip code": 1) = collection of the products combination index: {"_ id": ObjectId (...), "item": "Banana", "category": ["food", "produce", "grocery"], "location": "4th Street Store", "stock ": 4, "type": cases, "arrival": Date (...)} statement for creating a composite index: d B. products. ensureIndex ({"item": 1, "location": 1, "stock": 1}) = the value of a field indexed by multiple keys is an array, the index created on this field will index every element in the array. Example: {"_ id": ObjectId ("... ")," name ":" Warm John "," author ":" li ke "," tags ": [" weather "," hot "," record ", "l"] }== unique index: Example: create a unique index for user_id: db. addresses. ensureIndex ({"user_id": 1}, {unique: true}) === sparse indexdb. addresses. ensureIndex ({"xmpp_id": 1}, {sparse: true}) =========== parameters for creating an index === create an index in the background, does not affect the use of db for database instances. people. ensureIndex ({zipcode: 1}, {background: true, sparse: true}) = force the creation of a unique index db. accounts. ensureIndex ({username: 1}, {unique: true, dropDups: true })

Duplicate records will be deleted when force creation is performed!