我在nodejs中创建了mysql连接，它显示数据库已连接，但显示错误为未定义的数据库

Question

var mysql = require（＆＃39; mysql＆＃39;）;

var connection = mysql.createConnection（{

host : 'localhost',
user : 'root',
port : '3306',
password : 'root',
database : 'test'

}）;

connection.connect（函数（ERR）{

if(!err) {

    console.log("database is connected"+database);
} else {
    console.log("database is not connected"+err.message);
}

}）;

this is the error i got

Answer 1

将连接功能更改为如下所示:(用胖箭头功能替换功能＆＃34; =＆gt;＆＃34;）

connection.connect((err) => {
    if (!err) {
        console.log("database is connected"+database);
    } else {
        console.log("database is not connected"+err.message);
    }
});

以下链接解释了原因：

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