programmer group

The difference between Number() and new Number() and a simple implementation

When looking at the MDN Beginners document, I noticed the usage of var n1 = Number(123); the first question is that it is different from var n2 = new Number(123)   First, type of is used for detection. n1 is number and n2 is object. The essential difference between them is that they have different types   So the interesting question is, Number must know how to call it internally, and how to implement it?   The first thought is to...

programmer group

Basic usage of Sequelize

install $ npm install --save sequelize # You also need to install one of the following: $ npm install --save pg pg-hstore // postgreSql $ npm install --save mysql // mysql or mariadb $ npm install --save sqlite3 $ npm install --save tedious // MSSQL Establish connection const Sequelize = require('sequelize') const sequelize = new Sequelize(db.database, db.user, db.password, { //Table Name User Name Password host: db.host,...