A database is not updated if some values are not filled in the form

Question

I'm trying to update an SQL database from GUI. If I fill out all the fields in the form it works, but if any of the fields is NULL or empty nothing will update. No error is thrown, but database won't update in phpmyadmin. I want to be able to accept NULL and empty fields, including be able to erase content in a field.

I'm not a programmer so I'd appreciate explanations on how to deal with these empty fields.

<?php
include ("connection.php");
include ("foundation.php");
?>

<!DOCTYPE html>
<html>
    <head>
        <title>PHP UPDATE DATA USING PDO</title>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
    </head>
    <body>
        <form name="frmUser" method="post" action="">
            <input type="text" name="id" required placeholder="id"><br><br>
            <input type="text" name="person" required placeholder="person"><br><br>
            <input type="text" name="dob" required placeholder="dob"><br><br>
            <input type="text" name="dod" required placeholder="dod"><br><br>
            <input type="submit" name="update" required placeholder="Update Data">
        </form>
    </body>
</html>

<?php
if(isset($_POST['update']))
{
    // get values from input text and number
    $id = $_POST['id'];
    $person = $_POST['person'];
    $dob = $_POST['dob'];
    $dod = $_POST['dod'];
    
    // mysql query to Update data
    
    $pdoquery = "UPDATE people SET id=:id, person=:person,dob=:dob,dod=:dod WHERE id='" . $_GET['id'] . "'";
    $pdoQuery_run = $pdocbcon->prepare($pdoquery);
    $pdoQuery_exec = $pdoQuery_run->execute(array(":person"=>$person,":dob"=>$dob,":dod"=>$dod,":id"=>$id));
    
    if($pdoQuery_exec)
    {
        echo 'Uppdaterat';
    }
    else
    {
        echo 'FEL';
    }

}

?>

Do you want to update with empty value or you want to ensure that the field's are not empty at all? — Kazi Mohammad Ali Nur Romel, Mar 13 '21 at 07:59
But you need the id field to update anything. That field can not be null. I have changed my answer. Please check. — Kazi Mohammad Ali Nur Romel, Mar 13 '21 at 08:04
That’s right. ID is the only field that can never be NULL. — Jimmy Morén, Mar 13 '21 at 08:13
The others can be null yes. When I click submit I want to update all fields displayed no matter if the value is null or not. — Jimmy Morén, Mar 13 '21 at 08:24
Where did you get that "null" thing? Why do you think there is any null value involved? A null is a special type in PHP, and there is not a single null value in this code. — Your Common Sense, Mar 13 '21 at 08:37
do you get that "FEL" output of yours when the database is "not updated"? — Your Common Sense, Mar 13 '21 at 08:40
I don’t understand. Why would there be NULL values in the code? NULL is an input value (that I want to allow). As it is now I can’t update the database if one or more of the input fields are NULL. — Jimmy Morén, Mar 13 '21 at 09:07
There are NO NULL VALUES. The term "null" has a **very special meaning in programming**, it is not just synonym for "no value entered". What you have when a from input is not filled is an **empty string**. I am closing this question as a duplicate that explains how to get an error message from a database when your query doesn't work. Based on this error message, you will be able to resolve the issue. — Your Common Sense, Mar 13 '21 at 10:03
your query is wrong though. it should be `"UPDATE people SET person=:person,dob=:dob,dod=:dod WHERE id=:id"` — Your Common Sense, Mar 13 '21 at 10:14

Kazi Mohammad Ali Nur Romel · Answer 1 · 2021-03-13T08:10:32.960

-1

ID value cannot be null so in front end it must be inserted and in database you need to allow null for all the other columns.

if(isset($_POST['update']))
{
    // get values from input text and number
    $id = $_POST['id'];
    $person = $_POST['person'];
    $dob = $_POST['dob'];
    $dod = $_POST['dod'];

 if(empty($id)){
            echo("Missing Information! You must input ID");

edited Mar 13 '21 at 08:10

answered Mar 13 '21 at 08:02

Kazi Mohammad Ali Nur Romel

15,301
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There are no null values in this code, therefore it has nothing to do with the question asked – Your Common Sense Mar 13 '21 at 08:35
You are right. There are empty strings only. – Kazi Mohammad Ali Nur Romel Mar 13 '21 at 10:12

A database is not updated if some values are not filled in the form

1 Answers1