Select All Data from table Where Date is This Monday - php

Question

I have a date fields in database that have the day of the entry. The fields are starttime and stoptime, which define their schedule
For today of posting the start time is 2018-12-17 00:00:00 and the stop time is 2018-12-17 11:59:59
Example start times:
2018-12-17 15:30:00,
2018-12-24 06:00:00,
2018-12-17 10:00:00,
2018-12-17 09:00:00
and stop times (in the same order)
2018-12-17 16:00:00,
2018-12-24 07:00:00,
2018-12-17 12:30:00,
2018-12-17 10:30:00
it will show only 2018-12-17 09:00:00/2018-12-17 10:30:00
or everything else but the 1 above if i switch up the operation signs in if statement.
$starttime = date("Y-m-d H:i:s", strtotime('last monday', strtotime('next sunday')));
$stoptime = strtotime(date("Y-m-d H:i:s", strtotime($starttime))) + 43199;
$stoptime = date("Y-m-d H:i:s", $stoptime);
$stmt2 = $db->prepare("SELECT * FROM schedule WHERE day = :day");
$stmt2->execute(array(':day' => "Monday"));
while($row2 = $stmt2->fetch()){
if($row2['starttime'] >= $starttime AND $row2['stoptime'] <= $stoptime){
//data gets displayed here.
}
}

Answer 1

It looks like you have a misinterpreted date/time. From what you are supplying of 43199, this is 1 second LESS then 12HOURS, not a 24 hour day. So what you are getting are those entries that are before 12 mid-day time instead of 12 in the morning. On a 24-hour clock you would be at 86,400 for 24 hours... or 86,399 for 1 second less.
Additionally, you could update your query to just care about the start time as anytime within the starting date in question. If the ending time happens to roll-over to the next date, I am sure you want that in the result set too.
SELECT *
FROM schedule
WHERE startTime >= '2018-12-17'
and starttime < date_add( '2018-12-17', interval 7 days)
Now, I am doing LESS than 7 days in the above sample. So lets look at it.. The beginning date/time of '2017-12-17' is IMPLIED at hour:min 00:00 at midnight. By doing LESS than 7 days, it covers the entire week up to 11:59:59 PM (or 24hour clock 23:59:59) on the following Sunday. So it will be all LESS then Monday of the following week. Then you don't have to worry about formatting your specific strings in the query and then testing. Just get the results and go.