对数据可视化对研究2
node.js原⽣驱动
// mysql.js
const mysql = require("mysql");
// 连接配置
const cfg = {
host: "localhost",
user: "root",
password: "example", // 修改为你的密码
database: "kaikeba" // 请确保数据库存在
};
// 创建连接对象
const conn = mysql.createConnection(cfg);
// 连接
conn.connect(err => {
if (err) {
throw err;
} else {
console.log("连接成功!");
}
});
// 查询 conn.query()
// 创建表
const CREATE_SQL = `CREATE TABLE IF NOT EXISTS test (
id INT NOT NULL AUTO_INCREMENT,
message VARCHAR(45) NULL,
PRIMARY KEY (id))`;
const INSERT_SQL = `INSERT INTO test(message) VALUES(?)`;
const SELECT_SQL = `SELECT * FROM test`;
conn.query(CREATE_SQL, err => {
if (err) {
throw err;
}
// 插⼊数据
conn.query(INSERT_SQL, "hello,world", (err, result) => {
if (err) {
throw err;
}
console.log(result);
conn.query(SELECT_SQL, (err, results) => {
console.log(results);
conn.end(); // 若query语句有嵌套,则end需在此执⾏
})开课吧web全栈架构师
});
});
ES2017写法
// mysql2.js
(async () => {
// get the client
const mysql = require('mysql2/promise');
// 连接配置
const cfg = {
host: "localhost",
user: "root",
password: "example", // 修改为你的密码
database: "kaikeba" // 请确保数据库存在
};
// create the connection
const connection = await mysql.createConnection(cfg);
// 查询 conn.query()
// 创建表
const CREATE_SQL = `CREATE TABLE IF NOT EXISTS test (
id INT NOT NULL AUTO_INCREMENT,
message VARCHAR(45) NULL,
PRIMARY KEY (id))`;
const INSERT_SQL = `INSERT INTO test(message) VALUES(?)`;
const SELECT_SQL = `SELECT * FROM test`;
// query database
let ret = await connection.execute(CREATE_SQL);
console.log('create:', ret)
ret = await connection.execute(INSERT_SQL, ['abc']);
console.log('insert:', ret)
const [rows, fields] = await connection.execute(SELECT_SQL);
console.log('select:', rows)
})()