My view attendance table not pulling table from Database - php

Question

When I attempt to view an attendance that was already filled, it brings up the table, but it is empty. My SQL and Apache error logs do not give any errors and as far as im concerned, the database table names do match.
This is my PHP code for the View All. I've also tried defining $date=date("Y-m-d); before the mysqli_query and changing the "where date=$_POST[date]" to "date=$date" but to no avail
<?php
include("includes/dbhA.inc.php");
include("includes/PresenceRoster.inc.php");
?>
<div class="panel panel-default">
<div class="panel panel-heading">
<h2>
<a class="btn btn-success" href="Add.php"> Add Students </a>
<a class="btn btn-info pull-right" href="AttendanceTable.php"> Back </a>
</h2>
<div class="panel panel-body">
<form action="AttendanceTable.php" method="post">
<table class="table table-striped">
<tr>
<th>#serial Number</th> <th>Student Name</th> <th>Roll Numbers</th> <th>Attendance Status</th>
</tr>
<?php
$result=mysqli_query($con, "select * from attendance_records where date=$_POST[date]");
$serialnumber=0;
$counter=0;
while($row=mysqli_fetch_array($result))
{
$serialnumber++;
?>
<tr>
<td> <?php echo $serialnumber; ?> </td>
<td> <?php echo $row['student_name']; ?>
</td>
<td> <?php echo $row['roll_number']; ?> </td>
<td>
<input type="radio" name="attendance_status[<?php echo $counter; ?>]" value="Present"> Present
<input type="radio" name="attendance_status[<?php echo $counter; ?>]" value="Absent"> Absent
</td>
</tr>
<?php
$counter++;
}
?>
</table>
<input type="submit" name="submit" value="Submit" class="btn btn-primary">
</form>
</div>
</div>
This is my PHP code for the page before the view attendance
<?php
include("includes/dbhA.inc.php");
include("includes/PresenceRoster.inc.php");
?>
<div class="panel panel-default">
<div class="panel panel-heading">
<h2>
<a class="btn btn-success" href="Add.php"> Add Students </a>
<a class="btn btn-info pull-right" href="AttendanceTable.php"> Back </a>
</h2>
<div class="panel panel-body">
<table class="table table-striped">
<tr>
<th>Serial Number</th> <th>Dates</th> <th>Show Attendance</th>
</tr>
<?php
$result=mysqli_query($con, "SELECT distinct date FROM attendance_records");
$serialnumber=0;
while($row=mysqli_fetch_array($result))
{
$serialnumber++;
?>
<tr>
<td> <?php echo $serialnumber; ?> </td>
<td> <?php echo $row['date']; ?> </td>
<td>
<form action="show_attendance.php" method="POST">
<input type="hidden" value="<?php echo $row['date'] ?>" name="date">
<input type="submit" value="Show Attendance" class="btn btn-primary">
</form>
</td>
</tr>
<?php
}
?>
</table>
<input type="submit" name="submit" value="Submit" class="btn btn-primary">
</form>
</div>
</div>

Answer 1

You don't have any quotes, so your WHERE condition
where date=$_POST[date]
is expanded to where date=2019-02-17. MySQL happily computes 2019 - 2 - 17 = 2000. No date matches that so you get back zero records.
You should use a prepared statement for queries that take parameters like this, that way the database adds the necessary quotes and escape sequences http://php.net/manual/en/mysqli.quickstart.prepared-statements.php