Dependent Drop down list with just php and mysql - php

Question

I'm trying to create a dependent drop down list.in the code there are two select box one is department other being doctor.so what i want is if i select department 1 only the doctor in dept 1 with be in the option.what can i do?
what i wanted to do was using id ='iddept' from the department block and using it in the doctor's block.
<form class="" action="" method="post">
<select class="" name="deptname">
<?php
$deptsql=mysqli_query($con,"select deptname,deptid from department where status='1'");
while ($row = mysqli_fetch_assoc($deptsql))
{
echo "<option id='iddept' value='" . $row['deptid'] ."'>" . $row['deptname'] ."</option>";
}
?>
</select>
<br><br><br>
<label>select doctor</label>
<select class="" name="doc">
<?php
$dee=$_POST['iddept'];
echo $dee;
$docsql= mysqli_query($con,"SELECT * FROM doctor INNER JOIN department ON department.deptid=doctor.deptid WHERE department.deptid='$dee'");
while ($row = mysqli_fetch_assoc($docsql))
{ echo "<option value='" . $row['name'] ."'>" . $row['name'] ."</option>";
}
?>
</select>
</fieldset>
</form>
is it possible to this with just php and mysql?

Answer 1

Of course you can, having it set up this way. By the way, you can use a fixed id value in a loop operation as the id value must be unique in one html document.
As I get it, when you select a department, you need to submit the form. If so, then you can control what gets shown in the doctors dropdown. You don't even necessarily need to use join between tables, since you already have all information you need in the doctors table. Your second query would look like:
$docsql= mysqli_query($con, "SELECT * FROM doctor WHERE deptid = '$dee'");