echo inside if else in php - php

Question

I want to use echo inside if...else so i can print "-" if the data doesn't exist in the database, and if the data exist in database, print the data. Until now, my "-" doesn't shows up if the data doesn't exist in database.
This is for printing on localhost .php
<?php
$kata='';
$no=1;
$data = mysqli_query($koneksi,"SELECT msdosen.`IDDOSEN`, `POSITION`,
`COMPANY`, `START`, `END`
FROM trprofessionalhis
INNER JOIN msdosen ON msdosen.IDDOSEN = trprofessionalhis.IDDOSEN
WHERE trprofessionalhis.IDDOSEN ='$id'
ORDER BY trprofessionalhis.`START` DESC");
while($d = mysqli_fetch_array($data)){
?>
<br><?php echo $d['POSITION'];?><br><?php echo $d['COMPANY'];?>
<br><?php echo $d['START'];?>-<?php echo $d['END']?><br>
<?php
if (empty($d['POSITION'])){
echo '-';
}
else{
echo '';
}
}
?>
I expect the output prints "-" if the data doesn't exist in database.

Answer 1

You can use ternary operator. Here is example:
echo empty($d['POSITION']) ? $d['POSITION'] : '-';
If you are using PHP 7+ version, there is more short way:
echo $d['POSITION'] ?? '-';
More examples about ternary operator.

Answer 2

If your SQL query returns no result, $d will return NULL and the while-loop will end before it starts. Therefore none of the echo statements in the loop will be run.
Given the screenshot in this comment, I think this is the case. That is why your if-then never ran in the case intended and shows nothing:
As #catcon mentioned in comment, you can use mysqli_num_row to check if there is any result at all. That way you may still show something when there is no result:
<?php
$kata='';
$no=1;
$data = mysqli_query($koneksi,"SELECT msdosen.`IDDOSEN`, `POSITION`,
`COMPANY`, `START`, `END`
FROM trprofessionalhis
INNER JOIN msdosen ON msdosen.IDDOSEN = trprofessionalhis.IDDOSEN
WHERE trprofessionalhis.IDDOSEN ='$id'
ORDER BY trprofessionalhis.`START` DESC");
// add this to print "-" if the query returns no result
if (mysqli_num_row($data) <= 0) {
echo '<br> -';
}
?>
<?php while($d = mysqli_fetch_array($data)) { ?>
<br><?php echo $d['POSITION'];?><br><?php echo $d['COMPANY'];?>
<br><?php echo $d['START'];?>-<?php echo $d['END']?>
<?php } ?>