MongoDB_Commands

DataBases

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# Shell-Commands

# MongoDB Cheatsheet

// if database exists: switch to it - otherwise creates database
use test;  
 
// show/drop available databases
show databases;  
db.dropDatabase("test");
 
// show/create/drop collection
show collections;  
db.createCollection("any");  
db.any.drop();
 
 
db.any.remove({});  
 
// insert into collection
db.any.insertOne({  
    name: "Apple",  
    price: 0.99,  
}); 
db.any.insertMany(  
    [  
        {  
            name: "Plum",  
            price: 0.80,  
        },  
        {  
            name: "Kiwi",  
            price: 1.20,  
            ratings: [  
                { user: "Lassl", stars: 5},  
                { user: "Haul", stars: 4},  
                { user: "Muster", stars: 1}  
            ]  
        }  
    ]  
); 
  
// show all documents
db.any.find();
 
// selection - WHERE-statement
db.any.find({name: "Apple"});
db.any.find({age: 18});
// sorting ascending/descending
db.any.find().sort({name: 1});  // descending
db.any.find().sort({name: -1}); // ascending
 
// projection - show documents 
db.any.find({}, {name:0});  // show all fields - without field: name  
db.any.find({}, {name:1});  // show only _id-field & name-field 
 
// aggregate functions
// - count
db.any.find().count();
db.any.countDocuments();
 

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# MQL

The MongoDB Query Language supports a wide range of queries, including CRUD operations, aggregation, geospatial queries.

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