Understanding Differences in Query Behavior in mysql Connection Pools

const mysql=require("mysql");
const config = {
    host: '127.0.0.1',
    user: 'root',
    password:',
    database: "test",
    connectionLimit:10
}
const pool = mysql.createPool(config);
letstrQuery='SELECT* FROM `test';
// g Run query from getConnection
pool.getConnection(function(err,conn){
    if(err)throwerr;
    conn.query(strQuery, function(error, results, fields){
        if(error)throwerror;
        console.log(results);
        conn.release();
    });
});
// 直接 Run query directly
pool.query(strQuery, function(error, results, fields){
    if(error)throwerror;
    console.log(results);
});