How does Query.prototype.all() work in Mongoose ?
The Query.prototype.all() specifies an $all query condition. User can specify all values that has to be matched in an array passed as parameter.
Syntax:
Query.prototype.all()
Parameters: This function has two parameter, path and array of values.
Return Value: This function returns Query Object.
Installing mongoose :
npm install mongoose
After installing the mongoose module, you can check your mongoose version in command prompt using the command.
npm mongoose --version
After that, you can just create a folder and add a file for example, index.js as shown below.
Database: The sample database used here is shown below:
Example 1:
index.js
const mongoose = require( 'mongoose' ); // Database connection mongoose.connect( 'mongodb://127.0.0.1:27017/w3wiki' , { useNewUrlParser: true , useCreateIndex: true , useUnifiedTopology: true }); // User model const User = mongoose.model( 'User' , { name: { type: String }, age: { type: Number } }); User.find().all( 'name' ,[ 'Gourav' ]) .exec( function (error, result) { if (error) { console.log(error) } else { console.log(result) } }); |
The project structure will look like this:
Run index.js file using below command:
node index.js
Output:
[ { _id: 5ebb9129a99bde77b2efb809, name: ‘Gourav’, age: 10, __v: 0 } ]
Example 2:
index.js
const express = require( 'express' ); const mongoose = require( 'mongoose' ); const app = express() // Database connection mongoose.connect( 'mongodb://127.0.0.1:27017/w3wiki' , { useNewUrlParser: true , useCreateIndex: true , useUnifiedTopology: true }); // User model const User = mongoose.model( 'User' , { name: { type: String }, age: { type: Number } }); User.find().all( 'age' , [25]) .exec( function (error, result) { if (error) { console.log(error) } else { console.log(result) } }); app.listen(3000, function (error ){ if (error) console.log(error) console.log( "Server listening on PORT 3000" ) }) |
The project structure will look like this:
Run index.js file using below command:
node index.js
Output:
Server listening on PORT 3000
[ { _id: 5ebc3669a99bde77b2efb9ba, name: ‘Lalit’, age: 25, __v: 0 } ]
Reference: https://mongoosejs.com/docs/api/query.html#query_Query-all