con.query(stm, function(err, results){
    if (err) throw err;
    for(var i = 0; i < results.length; i++){
        var d = new Date(results[i].date);
        console.log(d);
        console.log(d.getDate())
    }
    console.log(results);

2018-06-12T17:00:00.000Z
13
2018-07-06T17:00:00.000Z
7
[ RowDataPacket {
date: 2018-06-12T17:00:00.000Z},
RowDataPacket {
date: 2018-07-06T17:00:00.000Z } ]