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Mongodb Overview

Installation :

Download Mongodb from below location

Custom installation, in order to set a simple installation location like C:\Manab\MongoDB

Set the Environment Variable(PATH) as below


Run :

mongod.exe --dbpath C:\Manab\MongoDB\data

Open another command prompt and navigate to the below location

C:\>cd C:\Manab\MongoDB\Server\3.0\bin

and type mongo.exe

Useful commands :

>show dbs : To check all the dbs exist in your mongodb server

>db.hostInfo() : To get the host information

>db.stats() :-To get stats about mongodb server type

>use fastcuredb :-To create database,It will not display in 'show dbs' list, until have any document

>db :-To check your currently selected database

>db.delete.insert({"name":"Manab Sample DB"}) / db.delete.insert({"name":"Arpana Basu","location":"UK"})

>show collections :-To see all the collections in the db

>db.createCollection("delete2") :-To create a new collection

>db.createCollection("delete3", { capped : true, autoIndexID : true, size : 6142800, max : 10000 } ) :-Create collection with parameter, can be seen by 'db.delete3.stats()'

>db.COLLECTION_NAME.find() /db.COLLECTION_NAME.find().pretty():-To query data either non formatted or formatted way(pretty), i.e db.delete.find()

>db.delete.find({"name":"Arpana Basu"}) /db.delete.find({"name":/Arpana/})/ db.delete.find({"name":/.*Arpana.*/,"location":"UK"}) /db.delete.find().limit(1)/db.delete.find().limit(1).skip(1)/db.delete.find().limit(1).sort({"name":-1})

>db.delete.update({"name":"Arpana Basu"},{$set:{"name":"Arpana B","location":"England"}})

>db.delete.remove({"name":"Arpana B"}) /db.delete.remove({"name":"Arpana B"},1)/ db.delete.remove()

-db.delete.update({"name":"Arpana Basu"},{$set:{"age":30}})
-db.delete.update({"name":"Manab Sample DB"},{$set:{"location":"UK","age":34}})

>db.delete.aggregate([{$group : {_id : "$location", people : {$sum : 1}}}])--Sum of people group by Country
db.delete.aggregate([{$group : {_id : "$location", people : {$avg : 1}}}])--avg of people group by Country

>db.COLLECTION_NAME.drop() :- To delete collection i.e db.delete3.drop()

>db.dropDatabase :-to drop a existing database


Additional DB level commands :

        db.adminCommand(nameOrDocument) - switches to 'admin' db, and runs command [ just calls db.runCommand(...) ]
        db.auth(username, password)
        db.commandHelp(name) returns the help for the command
        db.copyDatabase(fromdb, todb, fromhost)
        db.createCollection(name, { size : ..., capped : ..., max : ... } )
        db.currentOp() displays currently executing operations in the db
        db.eval() - deprecated
        db.fsyncLock() flush data to disk and lock server for backups
        db.fsyncUnlock() unlocks server following a db.fsyncLock()
        db.getCollection(cname) same as db['cname'] or db.cname
        db.getLastError() - just returns the err msg string
        db.getLastErrorObj() - return full status object
        db.getMongo() get the server connection object
        db.getMongo().setSlaveOk() allow queries on a replication slave server
        db.getProfilingLevel() - deprecated
        db.getProfilingStatus() - returns if profiling is on and slow threshold
        db.getSiblingDB(name) get the db at the same server as this one
        db.getWriteConcern() - returns the write concern used for any operations on this db, inherited from server object if set
        db.hostInfo() get details about the server's host
        db.isMaster() check replica primary status
        db.killOp(opid) kills the current operation in the db
        db.listCommands() lists all the db commands
        db.loadServerScripts() loads all the scripts in db.system.js
        db.runCommand(cmdObj) run a database command.  if cmdObj is a string, turns it into { cmdObj : 1 }
        db.setProfilingLevel(level,) 0=off 1=slow 2=all
        db.setWriteConcern( ) - sets the write concern for writes to the db
        db.unsetWriteConcern( ) - unsets the write concern for writes to the db
        db.setVerboseShell(flag) display extra information in shell output
        db.version() current version of the server

Additional Collection Level Commands :

        db.test.find().help() - show DBCursor help
        db.test.copyTo(newColl) - duplicates collection by copying all documents to newColl; no indexes are copied.
        db.test.convertToCapped(maxBytes) - calls {convertToCapped:'test', size:maxBytes}} command
        db.test.distinct( key ) - e.g. db.test.distinct( 'x' )
        db.test.drop() drop the collection
        db.test.dropIndex(index) - e.g. db.test.dropIndex( "indexName" ) or db.test.dropIndex( { "indexKey" : 1 } )
        db.test.explain().help() - show explain help
        db.test.find([query],[fields]) - query is an optional query filter. fields is optional set of fields to return.
                                                      e.g. db.test.find( {x:77} , {name:1, x:1} )
        db.test.findAndModify( { update : ... , remove : bool [, query: {}, sort: {}, 'new': false] } )
        db.test.getDB() get DB object associated with collection
        db.test.getPlanCache() get query plan cache associated with collection
        db.test.getIndexes() { key : ..., initial: ..., reduce : ...[, cond: ...] } )
        db.test.mapReduce( mapFunction , reduceFunction , )
        db.test.aggregate( [pipeline], ) - performs an aggregation on a collection; returns a cursor
        db.test.renameCollection( newName , ) renames the collection.
        db.test.runCommand( name , ) runs a db command with the given name where the first param is the collection name
        db.test.stats({scale: N, indexDetails: true/false, indexDetailsKey: , indexDetailsName: })
        db.test.storageSize() - includes free space allocated to this collection
        db.test.totalIndexSize() - size in bytes of all the indexes
        db.test.totalSize() - storage allocated for all data and indexes
        db.test.update(query, object[, upsert_bool, multi_bool]) - instead of two flags, you can pass an object with fields: upsert, multi
        db.test.validate( ) - SLOW
        db.test.getShardVersion() - only for use with sharding
        db.test.getShardDistribution() - prints statistics about data distribution in the cluster
        db.test.getSplitKeysForChunks( ) - calculates split points over all chunks and returns splitter function
        db.test.getWriteConcern() - returns the write concern used for any operations on this collection, inherited from server/db if set
        db.test.setWriteConcern( ) - sets the write concern for writes to the collection
        db.test.unsetWriteConcern( ) - unsets the write concern for writes to the collection

Mongodb Datatype :
MongoDB supports many datatypes whose list is given below:

String : This is most commonly used datatype to store the data. String in mongodb must be UTF-8 valid.
Integer : This type is used to store a numerical value. Integer can be 32 bit or 64 bit depending upon your server.
Boolean : This type is used to store a boolean (true/ false) value.
Double : This type is used to store floating point values.
Min/ Max keys : This type is used to compare a value against the lowest and highest BSON elements.
Arrays : This type is used to store arrays or list or multiple values into one key.
Timestamp : ctimestamp. This can be handy for recording when a document has been modified or added.
Object : This datatype is used for embedded documents.
Null : This type is used to store a Null value.
Symbol : This datatype is used identically to a string however, it's generally reserved for languages that use a specific symbol type.
Date  : This datatype is used to store the current date or time in UNIX time format. You can specify your own date time by creating object of Date and passing day, month, year into it.
Object ID : This datatype is used to store the document’s ID.
Binary data : This datatype is used to store binay data.
Code : This datatype is used to store javascript code into document.
Regular expression : This datatype is used to store regular expression

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