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MONGO

permitted SchemaTypes

Valid schema options new Schema({...}, options}

MongoDB connect

// MongoDB+srv connection string for cloud-based databases such as MongoDB Atlas
const uri = "mongodb+srv://username:password@cluster0.example.com/mydb";
const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });

// Advanced Connection String Options
mongodb://username:password@host1:27017,host2:27018,host3:27019/mydb?replicaSet=myReplicaSet&authSource=admin&ssl=true&connectTimeoutMS=300000&socketTimeoutMS=30000&readPreference=primaryPreferred

// enable TLS on a MongoDB server
mongod --tlsMode requireTLS --tlsCertificateKeyFile /path/to/your/cert.pem

// check db size
use yourDatabaseName
var stats = db.stats()
print("Database Size: " + (stats.dataSize / (1024 * 1024 * 1024)).toFixed(2) + " GB"); // Database Size: 1.75 GB
print("Storage Size: " + (stats.storageSize / (1024 * 1024 * 1024)).toFixed(2) + " GB"); // Storage Size: 2.00 GB

// db.collection.stats()
{
  size: 12345646,
  totalIndexSize: 1345641561,
}


// user access
$ mongo
$ use admin
db.createUser({
    user: "myAdminUser",
    pwd: "myAdminPassword",
    roles: [{ role: "userAdminAnyDatabase", db: "admin" }, "readWriteAnyDatabase"]
});
db.createUser({
  user: "myReadOnlyUser",
  pwd: "password",
  roles: [
    { role: "read", db: "myDatabase" },
  ]
});
db.grantRolesToUser('myReadOnlyUser', [
  { role: 'readWrite', db: 'myDatabase' }
])
db.createRole({
  role: 'readAndBackup',
  privileges: [
    { resource: { db: 'myDatabase', collection: '' }, actions: [ 'find', 'backup' ] }
  ],
  roles: []
})
db.grantRolesToUser('myReadOnlyUser', ['readAndBackup'])
db.revokeRolesFromUser('myReadOnlyUser', ['readWrite'])

// view user roles
$ use myDatabase
$ db.getUsers()
$ db.getRoles()

// change user password
$ db.changeUserPassword("root", "newpassword")
$ db.updateUser("root", {pwd: "newRootPassword"});
// then connect
$ mongo -u myAdminUser -p myAdminPassword --authenticationDatabase admin

// Constructing ObjectId with Specific Time
const date = new Date('2023-01-01T00:00:00Z');
const objectIdFromDate = ObjectId(Math.floor(date.getTime() / 1000).toString(16) + '0000000000000000');

const timestamp = document._id.getTimestamp();
// returns JavaScript `Date` object

// advanced date query
db.collection.aggregate([
    { 
        $project: {
            year: { $year: '$date' },
            month: { $month: '$date' },
            day: { $dayOfMonth: '$date' },
            hour: { $hour: '$date' }
        }
    },
    { 
        $match: {
            hour: 10
        }
    }
])

db.collection.findAndModify({
  query: { <query> },
  update: { <update> },
  remove: <boolean>,
  new: <boolean>,
  upsert: <boolean>,
  sort: { <fields> },
  fields: { <fields> }
})

{
  "_id": 1,
  "title": "First Post",
  "comments": [
    { "author": "Jane", "text": "Great post!" }
  ]
}
db.posts.findOneAndUpdate(
  { _id: 1, "comments.author": "Jane" },
  { $set: { "comments.$.author": "John" } },
  { returnNewDocument: true }
);

mongodb array operations

mongodb index operation

The ESR (Equality, Sort, Range) Rule 
// create single field index
db.users.createIndex({ username: 1 })
// Verifying the Index
db.users.getIndexes()

// To check the size of your indexes
db.collection.totalIndexSize()
// 4617080000  // 4.3 gigabytes

// create compound index
db.users.createIndex({ username: 1, email: 1 })
//

Executing Mongodb file script & geneal management

// Access shell
mongo

// check configuration of the MongoDB server
db.serverCmdLineOpts()

// Load and execute the script
load("/path/to/your/queries.js")

// Passing Command-Line Arguments
mongo --nodb --shell --eval "var name='MongoDB'; var age=10" /path/to/your/queries_with_args.js

// Add a cron job that runs 'queries.js' every day at 3 a.m.
0 3 * * * mongo database_name /path/to/your/queries.js

// Stopping MongoDB on Unix-like systems
sudo service mongod stop

// Stopping MongoDB on Windows 
net stop MongoDB

// Move the existing data to the new directory, ensuring permissions are adequate
sudo mv /data/db /new/directory/path
sudo chown -R mongodb:mongodb /new/directory/path

// restart with new dbpath
mongod --dbpath /new/directory/path
// For Windows, edit the MongoDB/config-file and adjust the dbpath value:
dbpath=C:\new\directory\path

// mv db by script
#!/bin/bash

stop_mongodb() {
    echo "Stopping MongoDB service..."
    sudo service mongod stop
}

move_data_files() {
    echo "Moving MongoDB data files..."
    sudo mv /data/db /new/directory/path
    sudo chown -R mongodb:mongodb /new/directory/path
}

update_db_path() {
    echo "Updating dbPath in MongoDB config..."
    sudo sed -i 's|/data/db|/new/directory/path|g' /etc/mongod.conf
}

start_mongodb() {
    echo "Starting MongoDB service with new dbPath..."
    sudo service mongod start
}

stop_mongodb
move_data_files
update_db_path
start_mongodb

echo "MongoDB data migration completed."

Sync to ES

replica configuration

rs.status()
rs.reconfig({ _id: "rs0", members: [{ _id: 0, host: "192.168.1.9:8094" }, { _id: 1, host: "192.168.1.9:8095" }, { _id: 2, host: "192.168.1.9:8096" }]}, { force: true })

mongodump & mongorestore on a replica set

mongorestore --uri="mongodb://192.168.0.58:8054,192.168.0.58:8055,192.168.0.58:8056/dbanme?replicaSet=rs0" --gzip dump/

mongodump --uri="mongodb://<db_user>:<db_passwd>@106.14.254.1:8054,106.14.254.1:8055,106.14.254.1:8056/dbanme?replicaSet=rs0" --collection=invoices --out=dump

[db operate]

# drop database
mongo <dbname> --eval "db.dropDatabase()"

# in mongodb console
> use mydb; 
> db.dropDatabase();

docker-compose

version: "3.6"
services:
  mongo1:
    image: "mongo:4.2"
    container_name: mongo1
    hostname: mongo1.example.com
    command: ["--replSet", "rs", "--bind_ip_all", "--wiredTigerCacheSizeGB", "1"]
    ports:
      - 8031:27017
    volumes:
      - /mnt/ssd/mongo-replica/mongod.conf:/etc/mongod.conf
      - /mnt/ssd/mongo-replica/node1:/data/db
    networks:
      my-net:
        ipv4_address: 172.16.8.6

  mongo2:
    image: "mongo:4.2"
    container_name: mongo2
    hostname: mongo2.example.com
    command: ["--replSet", "rs", "--bind_ip_all", "--wiredTigerCacheSizeGB", "1"]    
    ports:
      - 8032:27017
    volumes:
      - /mnt/ssd/mongo-replica/mongod.conf:/etc/mongod.conf
      - /mnt/ssd/mongo-replica/node2:/data/db
    networks:
      my-net:
        ipv4_address: 172.16.8.7

  mongo3:
    image: "mongo:4.2"
    container_name: mongo3
    hostname: mongo3.example.com
    command: ["--replSet", "rs", "--bind_ip_all", "--wiredTigerCacheSizeGB", "1"]    
    ports:
      - 8033:27017
    volumes:
      - /mnt/ssd/mongo-replica/mongod.conf:/etc/mongod.conf
      - /mnt/ssd/mongo-replica/node3:/data/db
    networks:
      my-net:
        ipv4_address: 172.16.8.8

  postgres:
    image: postgres:alpine
    container_name: postgres
    environment:
      - POSTGRES_PASSWORD=$POSTGRES_PASSWORD
      - POSTGRES_DB=$POSTGRES_DB
      - POSTGRES_USER=$POSTGRES_USER
    restart: always
    volumes:
      - /mnt/ssd/postgres:/var/lib/postgresql/data
    ports:
      - "15432:5432"
    networks:
      my-net:
        ipv4_address: 172.16.8.9

networks:
  my-net:
    name: "net_optimize"
    ipam:
      driver: default
      config:
        - subnet: "172.16.8.0/24"