如何根据要求在当天给予条件

Question

Here I am developing a logic, In which i want to give condition on Hour as per requirement, Example: Consider,

case 1: If hours is in between 17 to 20 then it will perform operation on date as date-1

case2: If not it will show date as it is

following query I have design but it doesn't work..:( provide me better solution...Thank You!

<?php
$mysqli = mysqli_connect('localhost','root','','company');
if (mysqli_connect_errno($mysqli)){
    echo "Failed to connect to MySQL:".mysqli_connect_error();
  }
$arr=array();

$query=mysqli_query($mysqli, "SELECT substr(date,1,2) as DAY,substr(date,4,2) as MONTH,substr(date,7,4) as YEAR 
from tbl_users
where substr(time,1,2)=17 OR substr(time,1,2)=18 OR substr(time,1,2)=19 OR substr(time,1,2)=20 AND id=3");

while($d=mysqli_fetch_array($query, MYSQL_ASSOC))
{
     $arr[]=$d['DAY'];
     $arr[]=$d['MONTH'];
     $arr[]=$d['YEAR'];
     $arr[]=$d['HOUR'];
     $arr[]=$d['MINUTE'];

}
$time=$arr[3]-1;
echo $time;
?>

Answer 1

Following my comment, you must check the condition at the PHP level rather than on queries. retrieve date and time from table and then check for condition on values retrieved

$query=mysqli_query($mysqli, "SELECT date, time from tbl_users where id=3");

while($d = mysqli_fetch_array($query, MYSQL_ASSOC))
{
   $day = date('D', strtotime($d['date']));
   //or you may use substr here instead of writing them in queries
}