CRUD

Query first approach

const updateCourse = async(id) =>{
	const course = await Course.findById(id);
	if(!course) return;
	couse.isPublished = false;
	course.author = "Michael";
	const result = await course.save();
	console.log(result);
}
updateCourse('123456798asdf');

Update first approach

//method 1
const updateCourse = async(id) =>{
	const result = await Course.update({_id:id},{$set:{author:"Michael",isPublished:false});
	console.log(result);
}

//method 2
const updateCourse = async(id) =>{
	const result = await Course.findByIdAndUpdate(id,{$set:{author:"Michael",isPublished:false},{new:true});		//new set to true will get the updated document
	console.log(result);
}

//method 3
const updateCourse = async(id) =>{
	const result = await Course.updateOne({_id:id},{$set:{author:"Michael",isPublished:false},{new:true});
	console.log(result);
}
updateCourse('123456798asdf');

Update by passing in a new object

const updateCourse = async(id,obj) =>{
	const course = await Course.findById(id);
	if(!course) return;
	course.set(obj);	//this will replace only fields that is specified in the object
	const result = await course.save();
	console.log(result);
}
updateCourse('123456798asdf',{author:"Michael",isPublished:false});

Remove one Document

const removeCourse = async(id) =>{
	const result = await Course.deleteOne({_id:id});
	console.log(result);
}
removeCourse('123456798asdf');

//method 2: can get the removed document
const removeCourses = async(id) =>{
	const result = await Course.findByIdAndRemove({isPublished:cond});
	console.log(result);
}
removeCourse('123456798asdf');

Remove Many Documents

//will return the number of deleted documents
const removeCourses = async(cond) =>{
	const result = await Course.deleteMany({isPublished:cond});
	console.log(result);
}
removeCourses(false);