How to set date in mysql to null and not to 0000-00-00

Question

I just finished a login-system and added another table for the useres personal information. For this reason, I have som inputs which aren't required. Textfields are nor problem but there is a problem with date and numberfields: Since the User isn't forced to give all the information fields that aren't filledin should be NULL. But in case of date it alway gives me 0000-00-00 instead and in case of number its always 0.

I give you the whole code because I#m not sure about what is most important but I think its line 9, 10, 14-21, 73, 76

<?php

  $user_id = $_GET['id'];

  if(isset($_POST['add-personal-data'])){
    $geschlecht = $_POST['geschlecht'];
    $vorname = $_POST['vorname'];
    $nachname = $_POST['nachname'];
    $alter = $_POST['alter'];
    $input_date = $_POST['geburtsdatum'];
    $lieblingsziel = $_POST['lieblingsziel'];
    $beschreibung = $_POST['beschreibung'];

    if($input_date != null){
      $geburtsdatum = date("Y-m-d H:i:s",strtotime($input_date));
    } else {
      $geburtsdatum = NULL;
    }

    $beschreibung_statement = $pdo->prepare("INSERT INTO beschreibung (user_id, name, vorname, geschlecht, user_alter, geburtsdatum, lieblingsziel, beschreibung)
                                            VALUES ('$user_id', '$nachname', '$vorname', '$geschlecht', '$alter', '$geburtsdatum', '$lieblingsziel', '$beschreibung')");

    $user_control_statement = $pdo->prepare("SELECT * FROM user WHERE user_id = '$user_id'");
    $user_control_statement->execute();
    $user = $user_control_statement->fetch();

    if($user != NULL){

        $user_has_description_statement = $pdo->prepare("SELECT * FROM beschreibung WHERE user_id = '$user_id'");
        $user_has_description_statement->execute();
        $description = $user_has_description_statement->fetch();

        if($description == NULL){
          $beschreibung_statement->execute();
        } else {
          echo ('<div class="line fehler"><p> Dieser Benutzer besitzt bereits eine Beschreibung. </p></div>');
        }

    } else {
      echo ('<div class="line fehler"><p> Dieser Benutzer existiert nicht. </p></div>');
    }
  }

    echo $geschlecht . "<br>" . $vorname . "<br>" . $nachname . "<br>" . $alter . "<br>" . $geburtsdatum . "<br>" . $lieblingsziel . "<br>" . $beschreibung ;

?>
<main>
  <div class="line">

    <div class="register">

      <form method="post" action="?p=add-personal-data&id=<?php echo $user_id; ?>">

        <h2>Persönliche Daten</h2>
        <hr />
        <p>Daten, die du hier angibst, werden auf deinem Profil angezeigt.</p>

        <h4>Geschlecht</h4>
        <select name="geschlecht" class="datafield">
          <option>männlich</option>
          <option>weiblich</option>
          <option>anderes</option>
          <option selected>keine Angabe</option>
        </select>

        <h4>Vorname</h4>
        <input type="text" name="vorname" placeholder="Vorname" class="datafield" value="">

        <h4>Nachname</h4>
        <input type="text" name="nachname" placeholder="Nachname" class="datafield" value="">

        <h4>Alter</h4>
        <input type="number" name="alter" placeholder="Alter" class="datafield" value="">

        <h4>Geburtsdatum</h4>
        <input type="date" name="geburtsdatum" placeholder="Geburtsdatum" class="datafield" value="">

        <h4>Lieblingsziel</h4>
        <input type="text" name="lieblingsziel" placeholder="Lieblingsziel" class="datafield" value="">

        <h4>Beschreibung</h4>
        <textarea name="beschreibung" wrap="soft" class="datafield" rows="5" placeholder="Gib hier persönliche information, wie zum Beispiel Hobbies an."></textarea>

        <div>
          <input type="submit" name="add-personal-data" value="Speichern" class="submitbutton">
        </div>

      </form>
    </div>

  </div>
</main>

How can I set NULL to "geburtsdatum" and "user_alter" if the user doesn't give any information?

Answer 1

Set default value to NULL or you can simply insert NULL value if the user doesn't give any information. Plus if you set DEFAULT to NULL then you don't even need to assign it any value. It will automatically assign it NULL
You can add you insert query for NULL simply like this

INSERT INTO beschreibung (geburtsdatum, user_alter, ...) VALUES (NULL,NULL,...);

Still, if you face problems then you need to go to phpmyadmin and make it allow null by checking this checkbox

Update

As Mangesh Sathe defined in the comment section you need to change the type to DATETIME or TIMESTAMP instead of date

Answer 2

First of all set the default value of geburtsdatum column NULL in your database. Now I think it would be better if you use 2 query strings or both if and else for geburtsdatum. If date is null, then do not insert it in the query.

Like:

$insert_query = '';
if($input_date != null){
  $geburtsdatum = date("Y-m-d H:i:s",strtotime($input_date));
  $insert_query = "INSERT INTO beschreibung (user_id, name, vorname, geschlecht, user_alter, geburtsdatum, lieblingsziel, beschreibung)
                                        VALUES ('$user_id', '$nachname', '$vorname', '$geschlecht', '$alter', '$geburtsdatum', '$lieblingsziel', '$beschreibung')";
} else {
  // there is no geburtsdatum in the query.
  $insert_query = "INSERT INTO beschreibung (user_id, name, vorname, geschlecht, user_alter, lieblingsziel, beschreibung)
                                        VALUES ('$user_id', '$nachname', '$vorname', '$geschlecht', '$alter', '$lieblingsziel', '$beschreibung')"
}
$beschreibung_statement = $pdo->prepare($insert_query);

Answer 3

This is a solution outside prepare:

You set either $geburtsdatum to string NULL , or to the quoted (not only escaped) date.

if( $input_date != null ){
    $geburtsdatum = '"'.date("Y-m-d H:i:s",strtotime($input_date)).'"';
} else {
    $geburtsdatum = "NULL";
}

Then in the VALUES() part you write it without quotes:

VALUES ( ..., '$alter', $geburtsdatum, '$lieblingsziel', ... )

Answer 4

If your geburtsdatum column already set to accept NULL values and Default set to NULL, you should instead separate the db statement into 2.

$geburtsdatum = date("Y-m-d H:i:s",strtotime($input_date));

if($input_date != null){
  $beschreibung_statement = $pdo->prepare("INSERT INTO beschreibung (user_id, name, vorname, geschlecht, user_alter, geburtsdatum, lieblingsziel, beschreibung)
                                        VALUES ('$user_id', '$nachname', '$vorname', '$geschlecht', '$alter', '$geburtsdatum', '$lieblingsziel', '$beschreibung')");

} else {
  //this statement will assign NULL into geburtsdatum field
  $beschreibung_statement = $pdo->prepare("INSERT INTO beschreibung (user_id, name, vorname, geschlecht, user_alter, lieblingsziel, beschreibung)
                                        VALUES ('$user_id', '$nachname', '$vorname', '$geschlecht', '$alter', '$lieblingsziel', '$beschreibung')");
}