$ vi /home/example/scripts/sample.sql

create database testdb;

grant select, insert, update, delete on testdb.* to testuser@localhost
 identified by 'teSt.ps8d';
flush privileges;

use testdb;

create table counter(
  seqno    int unsigned not null auto_increment,
  logdate  date,
  today    int unsigned default '0',
  sum      int unsigned default '0',
  PRIMARY KEY (seqno)
) ENGINE=MyISAM auto_increment=1 default charset=utf8;

insert into counter values(1,'2019-12-10',0,0);

<?php
  $mysqli = new mysqli('localhost','testuser','teSt.ps8d','testdb');
  $mysqli->set_charset("utf8");

  $sql = 'select seqno,logdate,today,sum from counter where seqno=1';
  if ($result = $mysqli->query($sql)) {
    if ($row = $result->fetch_assoc()) {
      $logdate = $row['logdate'];
      $today   = $row['today'];
      $sum     = $row['sum'];

      $now = date('Y-m-d');
      if ($logdate==$now) {
        $today++;
      } else {
        $logdate=$now;
        $today=1;
      }
      $sum++;

      $sql = 'update counter set logdate=\''.$now.'\',today='.$today.',
        sum='.$sum.' where seqno=1';
      $res = $mysqli->query($sql);
    }
  }
  $mysqli->close();
  echo date('Y-m-d (D)').' Today\'s Access : '.$today.' Total : '.$sum;
?>