How to assign 0 For Null variable values in PHP

Question

I am making a form which will load leave already availed values from mysql database. But if the value is nothing it shows nothing in the output. But i need to show 0 in the ($avail field)for the null value how to get that what i have tried is

$sqls = "SELECT  (@days :=  a.days  + @days) AS availed_days,days from tblleaves a,(SELECT @days:=0) c where 
LeaveType = '$type' AND empid ='$eid' ORDER BY availed_days desc ";

$querys = $dbh -> prepare($sqls);
$querys->bindParam(':eid',$eid,PDO::PARAM_STR);
$querys->execute();
$results=$querys->fetchAll(PDO::FETCH_OBJ);
if($querys->rowCount() > 0)
{
foreach($results as $result)
{  
    $avail=($result->availed_days);
    //$actual=($result->days);

 ?>

 <input value=" <?php  echo $avail?>" id="avail_days" name="avail_days"  type="text"  >

KIKO Software · Accepted Answer · 2021-08-05 05:01:48Z

1

You can use:

$avail = $result->availed_days ?? 0;

This is the so-called Null coalescing operator.

If $result->availed_days is null it will use the zero.

answered Aug 5, 2021 at 5:01

KIKO Software

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4 Comments

Kulikarai GHSS Over a year ago

Thanks for your response sir, still i can't solve the issue

Kulikarai GHSS Over a year ago

still the echo value field doesn't show anything

Kulikarai GHSS Over a year ago

If one record is entered with value it shows the value perfectly.. without entering any records this issue occurs

KIKO Software Over a year ago

Sorry, I cannot run your code, and see what your problem is.

feskr · Accepted Answer · 2021-08-05 05:00:04Z

0

Assuming the value contains integers besides the possible NULL value. Cast it to an integer.

<?php echo intval($avail); ?>

Or

<?php echo (int) $avail; ?>

answered Aug 5, 2021 at 5:00

feskr

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1 Comment

Kulikarai GHSS Over a year ago

Thanks for your response sir, still i can't solve the issue

shivgre · Accepted Answer · 2021-08-06 11:23:26Z

0

Your problem seems to be when there is no data as it can't reach the code that initializes the $avail variable(You might wanna check your if condition).

As a workaround you can pre-assign $avail=0 before the if.

answered Aug 6, 2021 at 11:23

shivgre

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