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GuilhermeSantos001/mongodb.js

Created June 3, 2021 15:21
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Truly Mittal -> Learn MongoDB in 50 minutes (Crash Course 2020)
Raw
mongodb.js
/* Cheatsheet for MongoDB
Created by: Truly Mittal
Date: March 2019
*/
/* SHOW DATABASE */
show dbs
/* USE DATABASE */
use DATABASE_NAME
/* current database */
db
/* DROP(delete) DATABASE */
db.dropDatabase()
/* CREATE COLLECTION */
db.createCollection("COLLECTION_NAME", {OPTIONS})
/* DROP(delete) COLLECTION */
db.COLLECTION_NAME.drop()
/* INSERt document */
db.users.insert({
name: "Truly Mittal",
age: 29
})
/* gettings all documents */
db.COLLECTION_NAME.find()
/* pretty the output */
db.COLLECTION_NAME.find().pretty()
/* finding a document by _id */
db.users.find({ _id: ObjectId("5c4d7c52eb87a6e0e5fc8949") }).pretty()
/* Finding by a field, here it is name */
db.users.find({name: "Truly Mittal"}).pretty()
/* update document */
db.users.update(
{ name: "Truly Mittal" },
{ $set : { age: 29 } }
)
/* unset a field in document */
db.users.update(
{ name: "Truly Mittal" },
{ $unset : { age: "" } }
)
/* update and auto insert if document not present */
db.users.update(
{ name: "Truly Mittal" },
{ name: "Truly Mittal" },
{ upsert: true }
)
/* Remove a document */
db.COLLECTION_NAME.remove({query})
db.COLLECTION_NAME.deleteOne({query})
/* insert multiple documents */
db.users.insert(
[
{
name: "Jhon Doe",
age: 36,
colors: ["red", "black", "blue"],
address: {
city: "paris",
country: "france"
}
},
{
name: "Hans Down",
age: 46,
colors: ["yellow", "white"],
address: {
city: "london",
country: "uk"
}
},
{
name: "Eric Widget",
age: 31,
colors: ["red", "green", "purple"],
address: {
city: "new delhi",
country: "india"
}
},
{
name: "Indigo Violet",
age: 29,
colors: ["red", "black"],
address: {
city: "washington dc",
country: "us"
}
}
]
)
/* count the number of documents */
db.users.count() /* Number of documents */
/* limit the number of fetched records */
db.users.find().limit(2) /* limit the number of records */
/* skip the number of records */
db.users.find().skip(2)
/* sort the record by the key name (1 Asc, -1 DesC) */
db.users.find().sort({name: 1}) /* sorts the records in asc and desc */
/* Update Multiple docs */
db.users.updateMany(
{}, //Filter
{} //Updates
)
db.users.update(
{}, //Filter
{}, //Updates
{ multi: true } //required in options if using only update instead of updateMany
)
/* Change the Field Name */
db.users.updateMany(
{}, //Filter
{ $rename: { "colours" : "colors" } } //Updates
)
/* AND query */
db.users.find({
$and: [
{ name: "Indigo Violet" },
{ age: 29 }
]
})
/* OR query */
db.users.find({
$or: [
{ name: "Indigo Violet" },
{ age: 29 }
]
})
/* OR with Less than equal to query */
db.users.find({
$or: [
{ name: "John Doe" },
{ age: { $lte : 31 }}
]
})
/* not query */
db.users.find({
age: {
$not: {
$lt: 40
}
}
}).pretty()
/* array operations
adds the whole array as an element inside an array */
db.users.update(
{ name: "Truly Mittal" },
{ $addToSet : { colors: ["yellow", "pink"] } }
)
/* adds each element of the array as an element inside an array works as a SET */
db.users.update(
{ name: "Truly Mittal" },
{
$addToSet : {
colors: {
$each: ["yellow", "pink"]
}
}
}
)
/* repeat above also to show that NOTHING happens */
/* adds each element of the array as an element inside an array NOT works as a SET */
db.users.update(
{ name: "Truly Mittal" },
{
$push : {
colors: {
$each: ["yellow", "pink"]
}
}
}
)
/* removes all entries from the array */
db.users.update(
{ name: "Truly Mittal" },
{
$pull : { colors: ["yellow", "pink"] }
}
)
db.users.update(
{ name: "Truly Mittal" },
{
$pull : { colors: "yellow" } //removes all enteries of "yellow"
}
)
db.users.update(
{ name: "Truly Mittal" },
{
$pull : { colors: "pink" }
}
)
/* The $in operator selects the documents where the value of a field equals any value in the specified array. */
db.users.update(
{ },
{
$pull: {
colors: {
$in: [ "red", "black" ]
}
}
},
{ multi: true }
)
/* Increment Operator */
db.users.update(
{ name: "Truly Mittal" },
{
$inc : { age: 2 }
}
)
/* $pop */
db.users.update(
{name: "Indigo Violet" },
{ $set : {
scores: [ 3, 65, 2 ]
}}
)
db.users.update(
{name: "Indigo Violet" },
{ $pop : { scores: 1 } }
)
db.users.updateMany(
{ },
{
$push: {
colors: {
$each: [ "red", "black" ]
}
}
}
)
/* Setting the current date in field called "lastModified" */
db.inventory.updateOne(
{ name: "Truly Mittal" },
{ $currentDate: { lastModified: true } }
)
/*
The $currentDate operator sets the value of a field to the current date, either as a Date or a timestamp. The default type is Date.
{ $currentDate: { <field1>: <typeSpecification1>, ... } }
<typeSpecification> can be either:
1. a boolean true to set the field value to the current date as a Date, or
2. a document { $type: "timestamp" } or { $type: "date" } which explicitly specifies the type.
The operator is case-sensitive and accepts only the lowercase "timestamp" or the lowercase "date". */
/* Exporting in docs using mongoexport */
mongoexport --db DB_NAME --collection COLLECTION_NAME -o FILENAME.json
/* Exporting in docs using mongoexport as JSON ARRAY */
mongoexport --db DB_NAME --collection COLLECTION_NAME -o FILENAME.json --jsonArray
/* Importing Docs from a file */
mongoimport --db DB_NAME --collection COLLECTION_NAME --fileo FILENAME.json
/* Importing Docs from a file if it is formatted as a JSON ARRAY */
mongoimport --db DB_NAME --collection COLLECTION_NAME --fileo FILENAME.json --jsonArray
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