Mongoose SchemaType.prototype.index()用法及代碼示例

const mongoose = require("mongoose"); 
const { Schema } = mongoose; 
mongoose.set("strictQuery", true); 
const userSchema = new Schema({ 
    name: { 
        type: String, 
        required: true, 
    }, 
    email: { 
        type: String, 
        required: true, 
    }, 
    age: Number, 
    address: { 
        street: String, 
        city: String, 
        state: String, 
        zip: String, 
    }, 
}); 
  
// Creating indexes on the email and age fields 
userSchema.index({ email: 1 }, { unique: true }); 
userSchema.index({ age: 1 }); 
  
// Creating a compound index on the address fields 
userSchema.index({ "address.city": 1, "address.state": 1 }); 
  
// Creating a text index on the name and address fields 
userSchema.index({ 
    name: "text", 
    "address.street": "text", 
    "address.city": "text", 
    "address.state": "text", 
}); 
  
// Creating a 2dsphere index on the address field for  
// geo-spatial queries 
userSchema.index({ "address.coordinates": "2dsphere" }); 
  
// Creating a hashed index on the name field for  
//efficient sharding 
userSchema.index({ name: "hashed" }); 
  
// Creating a partial index on the age field for documents  
// where the age field is less than or equal to 30 
userSchema.index( 
    { age: 1 }, 
    { partialFilterExpression: { age: { $lte: 30 } } } 
); 
  
const User = mongoose.model("User", userSchema); 
  
// Connecting to a MongoDB database and creating a new user 
mongoose 
    .connect("mongodb://localhost:27017/geeksforgeeks", 
            { useNewUrlParser: true }) 
    .then(() => { 
        console.log("Connected to MongoDB"); 
  
        const newUser = new User({ 
            name: "John Doe", 
            email: "johndoe@example.com", 
            age: 25, 
            address: { 
                street: "123 Main St", 
                city: "Anytown", 
                state: "CA", 
                zip: "12345", 
            }, 
        }); 
  
        return newUser.save(); 
    }) 
    .then((user) => { 
        console.log(`Created new user: ${user.name}`); 
        mongoose.connection.close(); 
    }) 
    .catch((err) => console.error(err));

const mongoose = require("mongoose"); 
const { Schema } = mongoose; 
mongoose.set("strictQuery", true); 
const movieSchema = new Schema({ 
    title: { 
        type: String, 
        required: true, 
    }, 
    actors: [ 
        { 
            name: { 
                type: String, 
                required: true, 
            }, 
            character: { 
                type: String, 
                required: true, 
            }, 
        }, 
    ], 
}); 
  
// Creating a unique index on the 'actors.name' field within  
// the 'actors' subdocument array 
movieSchema.index({ "actors.name": 1 }, { unique: true }); 
  
const Movie = mongoose.model("Movie", movieSchema); 
  
// Connecting to a MongoDB database and creating a new user 
mongoose 
    .connect("mongodb://localhost:27017/geeksforgeeks",  
            { useNewUrlParser: true }) 
    .then(() => { 
        console.log("Connected to MongoDB"); 
  
        const newMovie = new Movie({ 
            title: "The Avengers", 
            actors: [ 
                { name: "Robert Downey Jr.", character: "Iron Man" }, 
                { name: "Chris Evans", character: "Captain America" }, 
                { name: "Robert Downey Jr.", character: "Tony Stark" },  
                // Duplicate actor name 
            ], 
        }); 
  
        return newMovie.save(); 
    }) 
    .then((movie) => { 
        console.log(`Created new movie: ${movie.title}`); 
        mongoose.connection.close(); 
    }) 
    .catch((err) => console.error(err));