Mongodb

Aggregation

//Aggregation Pipeline
// first match then sort and project name note : _id:0 couse not show _id if not set show _id
db.companies.aggregate([
    { $match : { founded_year : 2011 } },
    { $sort : {name:-1}  },
    { $project : { _id : 0, name : 1  } }
])
// query 2
db.companies.aggregate([
    { $match: { founded_year: { $gte: 2010 } } },
    { $group: {
        _id: "$founded_year",
        companies: { $push: "$name" }
    } },
    { $sort: { "_id": 1 } }
])
----------------------------------------------
Collections:
      Users
      User Subscriptions
//$lookup
db.Users.aggregate(
   [
	{
	    $lookup: {
		"from" : "UsersSubscriptions",
		"localField" : "_id",
		"foreignField" : "user_id",
		"as" : "subscriptions"
	    }
	},
   ]
);

//$group

db.user.aggregate({
	$group : {
  		_id:"$eyeColor"
  		total : {$sum:1}
	}
})

db.twitter.aggregate( 
		{ $group : { 
			"_id" : "$user.screen_name", 
			 "tweets" : { $sum : 1 } 
			} 
		},
		{ $sort : { "tweets" : -1 } },
		{ $limit : 5 } 
)

//Unwind
	//document
	{ "_id" : 1, "item" : "ABC1", sizes: [ "S", "M", "L"] }
	//query
	db.inventory.aggregate( [ { $unwind : "$sizes" } ] )
	//result
	{ "_id" : 1, "item" : "ABC1", "sizes" : "S" }
	{ "_id" : 1, "item" : "ABC1", "sizes" : "M" }
	{ "_id" : 1, "item" : "ABC1", "sizes" : "L" }
	
//UnWind and Group (first unwind then group it)
db.collection.aggregate({$unwind:"$NestedArray"},{$group:{"_id":"$NestedArray.FieldNAme","count":{$sum:1}}})
	//sample
	db.careers.aggregate({$unwind:"$neededSkills"},{$group:{"_id":"$neededSkills.skillBranch","count":{$sum:1}}})
	

Use Full Commands for MongoDB.txt

=====================================================================
//stop start mongo in linux
systemctl start mongod
systemctl stop mongod
systemctl restart mongod

install as service in windows: (run with administrator provilage)
mongod -f \mongodb\mongod.conf --install
// Import to databse
mongo dbName < collectionJson.js  - db.collection.insert([{...}{...}])

// Backup
mongodump
mongodump --out /data/backup/

//Restore
mongoresmongorestore dump

// Go shell
mongo 

// Show databases
show dbs

use foo

help

// Show collections
show collections
=================================== Find ==================================
// Find collections
db.collection.find()
db.foo.find().pretty() //prettify json
    //sample
    -----------------------------------------
//find in array in collection
 db.collection.find({arrayName: { $elemMatch: { field: "5a887b9395ffee023051ccfc" } } } )
        //sample
        db.careers.find({readyTalents: { $elemMatch: { userId: "5a887b9395ffee023051ccfc" } } } ).pretty()
        db.careers.find({readyTalents: { $elemMatch: { userId: "5a887b9395ffee023051ccfc",statuses:{$elemMatch: { id: "H1z-             aBPwz"}}}}).pretty()
         db.careers.find({readyTalents: { $elemMatch: { id: "H1z-aBPwz"}}}).pretty()
         //find array in document that not equal empty and sort it
         db.careers.find({readyTalents:{$ne:[]}},{readyTalents:1}).sort({readyTalents.statuses.date: -1})
         db.careers.find({readyTalents:{$ne:[]}},{readyTalents:1}).sort({"readyTalents.statuses.date": -1}).limit(1).pretty()
         


find and modify:
db.collection.findAndModify({
    query: <document>,
    sort: <document>,
    remove: <boolean>,
    update: <document>,
    new: <boolean>,
    fields: <document>,
    upsert: <boolean>,
    bypassDocumentValidation: <boolean>,
    writeConcern: <document>,
    collation: <document>
});

================================= Save and Insert ====================================
// Save and insert
db.foo.save({_id:1,value:'Hello World'}) 
db.foo.insert({{_id:1,value:'Hello World'}})
===================================== Update ================================
// Update syntax:
db.foo(collection).update(query(which document),update(what change?),options(one?Many?upsert?))
db.foo.update({_id:1},{$inc:{x:1}})
db.foo.update({_id:1},{$set:{y:3}}) // add column to a collection with value of 3
    //samples 
        db.careers.update({_id: ObjectId("5a23fe549032554c72af31d3")},{$set:{isApproved:true}}) //add or set
        db.talents.update({},{$set:{married:'single'},{ multi: true })
        //update nested  
        db.careers.update({"creatorTalent.userId":ObjectId("5a281ec5a636cb016e3d5390")},{$set:        {"creatorTalent.typeOfProductionOrService":"test"})
        db.students.updateOne(
           {
            _id: ObjectId(5a5d899d85d1bf6a45cbc9bd),
            readyTalents: { $elemMatch: { grade: { $lte: 90 }, mean: { $gt: 80 } } }
           },
           { $set: { "grades.$.std" : 6 } }
        )


db.foo.update({_id:1},{$unset:{y:0}}) // remove column y
db.a.update({_id:1},{$rename:{'Naem':'Name'}}) //rename column
db.a.update({_id:1},{$addToSet:{things:'two'}}) // add to array if not exist
db.a.update({_id:1},{$pull:{things:'one'}}) // pull one element from array
db.a.update({_id:1},{$pop:{things:1}}) //remove last elemt of array
db.a.update({_id:1},{$pop:{things:-1}}) //remove first elemt of array
// Update all
db.collection.update({},{$set:{createDate:new Date()}},{ multi: true })

// Push to array
//The following example appends 89 to the scores array:
db.students.update(
   { _id: 1 },
   { $push: { scores: 89 } }
)

//How to remove an element from a doubly-nested array in a MongoDB document
 temp {
"_id" : "777",
"someKey" : "someValue",
"someArray" : [
    {
        "name" : "name1",
        "someNestedArray" : [
        "someNestedArray" : [
            {
                "name" : "value"
            },
            {
                "name" : "delete me"
            }
        ]
    }
  ]
}
db.temp.update(
  { _id : "777" },
  {$pull : {"someArray.0.someNestedArray" : {"name":"delete me"}}}
)
//Imortant sample
//remove from array in document
db.talents.update({_id:ObjectId("5aedc7ce0702a52d509404f5")},{$pull:{jobsRequests:{id:"BJlvS9h26z"}}})
//16 is number of status in readyTalents array  in career collections
db.careers.update({_id:ObjectId("5ae416c5af0f737ad797783b")},{$pull:{"readyTalents.16.statuses":{id:"Bkv_TVuAz"}}})
//find array in document and add or set field on it
db.careers.updateOne({_id:ObjectId("5b38c8fe72d395408b84f35d"), "readyTalents.talentFamilyName": "test"},{$set:    {"readyTalents.$.id":"1"}})
//update many nested array without key
db.talents.updateMany({"jobsRequests.jobBranch":"خدمات و کارگری"},{$set:{"jobsRequests.$.jobBranch":"کارگری و خدمات"}})

// convert Object String to ObjectId
db.careers.find().forEach(function (x) {
     x.readyTalents.forEach(function (y) {
	   try {
			y.talentId = ObjectId(y.talentId);
		   }
	   catch (err) {}
     });
     db.careers.save(x);
 });
 

================================ Database =====================================
// Switched to db mydb
use mydb

// Drop Database:
db.dropDatabase()

=================================== Drop and Remove ==================================
// Drop Collection
db.collection.drop()
// Delete All Documents:
db.collection.deleteMany({})
db.collection.deleteMany({"name": "xxx"})
//remove or delete document
db.collection.remove({"_id": ObjectId("xxxx")});

====================================== Index ===============================
//show index on collections
 db.collection.getIndexes()
//Index size
  db.ships.totalIndexSize() 

//create index
db.collection.createIndex({key:value})
db.careers.createIndex( { "careerUniqueId": 1 }, { unique: true } ) //Unique Index
 Full Text Search:
 db.messages.createIndex({"subject":"text"})
 db.messages.find({$text: {$search: "dogs"}}, {score: {$meta: "toextScore"}}).sort({score:{$meta:"textScore"}})
    //sample
    db.users.createIndex({'name':'text','familyName':'text','cellphoneNumber':'text'}) //Text Index
//remove index
db.collection.dropIndex({key:value})
    //sample
    db.careers.dropIndex({"careerUniqueId" : 1})

//count
db.collection.count({field : 'xxxx'})

//distinct
db.collection.distinct({field : 'xxxx'})