General notes on this course will write here. This course seems to be more difficult than MongoDB for devs,at least 3 hours of lectures vs 1 hour is a great difference!
- Week1
- Week2
MongoImport works as follows:
serhii@serhii:~/Downloads$ mongoimport --db pcat --collection products < products.json
Homework 1.4: How would you print out, in the shell, the name of all the products without extraneous characters or braces, sorted alphabetically, ascending? (Check all that would apply.)
db.products.find({},{name:1,_id:0}).sort({name:1}) //output { "name" : "AC3 Case Black" } { "name" : "AC3 Case Green" } { "name" : "AC3 Case Red" } { "name" : "AC3 Phone" } { "name" : "AC3 Series Charger" } { "name" : "AC7 Phone" } { "name" : "Cable TV Basic Service Package" } { "name" : "Phone Extended Warranty" } { "name" : "Phone Service Basic Plan" } { "name" : "Phone Service Core Plan" } { "name" : "Phone Service Family Plan" } var c = db.products.find({},{name:1,_id:0}).sort({name:1}); while( c.hasNext() ) print( c.next().name); //reslut AC3 Case Black AC3 Case Green AC3 Case Red AC3 Phone AC3 Series Charger AC7 Phone Cable TV Basic Service Package Phone Extended Warranty Phone Service Basic Plan Phone Service Core Plan Phone Service Family Plan var c = db.products.find({}).sort({name:1}); c.forEach( function(doc){ print(doc.name) } ); //res AC3 Case Black AC3 Case Green AC3 Case Red AC3 Phone AC3 Series Charger AC7 Phone Cable TV Basic Service Package Phone Extended Warranty Phone Service Basic Plan Phone Service Core Plan Phone Service Family Plan var c = db.products.find({}).sort({name:-1}); while( c.hasNext() ) print( c.next().name); //res AC3 Case Black AC3 Case Green AC3 Case Red AC3 Phone AC3 Series Charger AC7 Phone Cable TV Basic Service Package Phone Extended Warranty Phone Service Basic Plan Phone Service Core Plan Phone Service Family Plan
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var t = db.products; t.save //outputs function ( obj , opts ){ if ( obj == null ) throw "can't save a null"; if ( typeof( obj ) == "number" || typeof( obj) == "string" ) throw "can't save a number or string" if ( typeof( obj._id ) == "undefined" ){ obj._id = new ObjectId(); return this.insert( obj , opts ); } else { return this.update( { _id : obj._id } , obj , Object.merge({ upsert:true }, opts)); } } //that means Function called if update doc like var x = db.products.find({_id : ObjectId("507d95d5719dbef170f15c00")}); x.term_years = 3; t.update({_id : x._id}, x); //same result t.save(x); //How many products have a voice limit? (That is, have a voice field present in the limits array.) db.products.find( { limits: { $exists: [ "voice"] } } ).count(); /*Quiz: Partial Updates & Document Limits The Mongo Web Shell has been initialized with one collection, cars, with one document preexisting: { "_id" : 100, "name" : "GTO", "year" : 1969, "color" : "red" } Set the available field to 1. */ db.cars.update({_id: 100}, {$set: {available: 1}}); //will romove "hello", "hellos, etc db.cars.remove({ x: /ell/});
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