show dbs
db
Create Or Switch Database use acme
db.dropDatabase()
db.createCollection('posts')
show collections
db.posts.insert({
title: 'Post One',
body: 'Body of post one',
category: 'News',
tags: ['news', 'events'],
user: {
name: 'John Doe',
status: 'author'
},
date: Date()
})
Insert Multiple Documents db.posts.insertMany([
{
title: 'Post Two',
body: 'Body of post two',
category: 'Technology',
date: Date()
},
{
title: 'Post Three',
body: 'Body of post three',
category: 'News',
date: Date()
},
{
title: 'Post Four',
body: 'Body of post three',
category: 'Entertainment',
date: Date()
}
])
db.posts.find()
Get All Documents Formatted db.posts.find().pretty()
db.posts.find({ category: 'News' })
# asc
db.posts.find().sort({ title: 1 }).pretty()
# desc
db.posts.find().sort({ title: -1 }).pretty()
db.posts.find().count()
db.posts.find({ category: 'news' }).count()
db.posts.find().limit(2).pretty()
db.posts.find().limit(2).sort({ title: 1 }).pretty()
db.posts.find().forEach(function(doc) {
print("Blog Post: " + doc.title)
})
db.posts.findOne({ category: 'News' })
db.posts.find({ title: 'Post One' }, {
title: 1,
author: 1
})
db.posts.update({ title: 'Post Two' },
{
title: 'Post Two',
body: 'New body for post 2',
date: Date()
},
{
upsert: true
})
db.posts.update({ title: 'Post Two' },
{
$set: {
body: 'Body for post 2',
category: 'Technology'
}
})
db.posts.update({ title: 'Post Two' },
{
$inc: {
likes: 5
}
})
db.posts.update({ title: 'Post Two' },
{
$rename: {
likes: 'views'
}
})
db.posts.remove({ title: 'Post Four' })
db.posts.update({ title: 'Post One' },
{
$set: {
comments: [
{
body: 'Comment One',
user: 'Mary Williams',
date: Date()
},
{
body: 'Comment Two',
user: 'Harry White',
date: Date()
}
]
}
})
Find By Element in Array ($elemMatch) db.posts.find({
comments: {
$elemMatch: {
user: 'Mary Williams'
}
}
}
)
db.posts.createIndex({ title: 'text' })
db.posts.find({
$text: {
$search: "\"Post O\""
}
})
db.posts.find({ views: { $gt: 2 } })
db.posts.find({ views: { $gte: 7 } })
db.posts.find({ views: { $lt: 7 } })
db.posts.find({ views: { $lte: 7 } })
$eq: Matches values that are equal to a specified value.
{ "age": { "$eq": 30 } }
$gt: Matches values that are greater than a specified value.
{ "age": { "$gt": 30 } }
$gte: Matches values that are greater than or equal to a specified value.
{ "age": { "$gte": 30 } }
$lt: Matches values that are less than a specified value.
{ "age": { "$lt": 30 } }
$lte: Matches values that are less than or equal to a specified value.
{ "age": { "$lte": 30 } }
$ne: Matches all values that are not equal to a specified value.
{ "age": { "$ne": 30 } }
$in: Matches any of the values specified in an array.
{ "age": { "$in": [30, 40] } }
$nin: Matches none of the values specified in an array.
{ "age": { "$nin": [30, 40] } }
$and: Joins query clauses with a logical AND and returns all documents that match the conditions of both clauses.
{ "$and": [{ "age": { "$gt": 20 } }, { "age": { "$lt": 40 } }] }
$or: Joins query clauses with a logical OR and returns all documents that match the conditions of either clause.
{ "$or": [{ "age": { "$lt": 20 } }, { "age": { "$gt": 40 } }] }
$not: Inverts the effect of a query expression and returns documents that do not match the query expression.
{ "age": { "$not": { "$gt": 30 } } }
$nor: Joins query clauses with a logical NOR and returns all documents that fail to match both clauses.
{ "$nor": [{ "age": { "$lt": 20 } }, { "age": { "$gt": 40 } }] }
$exists: Matches documents that have the specified field.
{ "age": { "$exists": true } }
$type: Selects documents if a field is of the specified type.
{ "age": { "$type": "number" } }
$expr: Allows the use of aggregation expressions within the query language.
{ "$expr": { "$gt": ["$qty", "$inStock"] } }
$Schema: Validate documents against the given Schema.
{ "$Schema": { "required": ["name", "email"] } }
$all: Matches arrays that contain all elements specified in the query.
{ "tags": { "$all": ["mongodb", "database"] } }
$elemMatch: Selects documents if the array field contains an element that matches all the specified query criteria.
{ "students": { "$elemMatch": { "name": "Alice", "grade": { "$gte": 80 } } } }
$size: Selects documents if the array field is a specified size.
{ "comments": { "$size": 5 } }
$: Projects the first element in an array that matches the query condition.
{ "scores": { "$elemMatch": { "$gt": 80 } } }
$elemMatch: Projects the first element in an array that matches the specified condition.
{ "students": { "$elemMatch": { "grade": { "$gt": 90 } } } }
$meta: Projects metadata such as the score of a document in a text search.
{ "score": { "$meta": "textScore" } }
$set: Sets the value of a field in a document.
{ "$set": { "status": "active" } }
$unset: Removes the specified field from a document.
{ "$unset": { "status": "" } }
$inc: Increments the value of a field in a document.
{ "$inc": { "quantity": 10 } }
$mul: Multiplies the value of a field in a document.
{ "$mul": { "price": 1.1 } }
$rename: Renames a field in a document.
{ "$rename": { "oldName": "newName" } }
$min: Only updates the field if the specified value is less than the existing field value.
{ "$min": { "price": 100 } }
$max: Only updates the field if the specified value is greater than the existing field value.
{ "$max": { "price": 200 } }
$currentDate: Sets the value of a field to the current date or time.
{ "$currentDate": { "lastModified": true } }
$: Acts as a placeholder to update the first element that matches the query condition in an array.
{ "$[elem]": { "score": { "$gt": 80 } } }
$[]: Updates all elements in an array.
{ "$[]": { "status": "done" } }
$[<identifier>]: Acts as a placeholder to update all elements that match the arrayFilters condition in an array.
{ "$[elem]": { "score": { "$gt": 80 } } }
