Model method

17 Model Method

Model It's a constructor

Model.create(doc(s),[callback])

Create a document and add it to the database

Parameters doc(s) Can be a document object , It can also be an array .

callback Optional Callback function that is called when the operation is completed. .

// Inquire about 
Model.find()

condition- Query criteria 
projection  Projection   Fields to get 
	 Two ways 
		{
    name:1,_id:0}
		"name age -_id"
option-- Query options  skip  limit
callback   Callback function    The callback function must pass , If not , Will not query .
// Always return an array 
StuModel.find({
    name:" Tang's monk "},function(err,docs){
    
    if(!err){
    
        console.log(docs);
    }
}
);

StuModel.find({
    },{
    name:1,_id:0},function(err,docs){
    
    if(!err){
    
        //doc yes Document Document object , yes model Example .
                  console.log(docs);
              }
}
);

StuModel.find({
    },"name age -_id",function(err,docs){
    
    if(!err){
    
            
        console.log(doc instanceof StuModel);
              }
}
);

modify

conditions   Query criteria 
doc   Modified objects 
options  Configuration parameters 
callback   Callback function 

StuModel.updateOne({
    name:" Tang's monk "},{
    $set:{
    age:20}},function(err){
    
    
    if(!err){
    
        console.log(" Modification successful ");
    }
});

Delete

StuModel.remove({
    name:" Bones jing "},function(err){
    
    if(!err){
    
        console.log(" Delete successful ");
    }
});

Statistical quantity Count

Model.count(conditions,[callback])

StuModel.count({},function(err,count){
	if(!err){
		console.log(count);
	}
});