How to delete data from database?

Question

I have this code to erase the data from the database where the name is the same as the one chosen on the combobox, whose code and the second. But for some reason I can’t figure out which one isn’t working. They can help me?

....
try {
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
if (isset($_POST['botao_apagar']))
{
$cbnome= trim($_POST['cbMedicos']);
$stmt = $conn->prepare("DELETE * FROM Medicos WHERE nome= '".$cbnome."' "); 
$stmt->execute();

// set the resulting array to associative
$result = $stmt->setFetchMode(PDO::FETCH_ASSOC);
}

}
catch(PDOException $e) {
echo "Error: " . $e->getMessage();
}
$conn = null;
?>

combobox code:

<label for="cbMedicos">Selecione um M&eacute;dico</label>
<select id="cbMedicos" name="cbMedicos">
<option>Selecione...</option>

<?php while($prod = $data->fetch_assoc()) { 
    echo '<option value="'.$prod['txtid'].'">'.$prod['txtNome'].'</option>';
    $meujson[$prod['txtid']] = $prod; // coleciona as linhas no $meujson


}
?>
</select>

Answer 1

It seems that your query delete is incorrect. The correct syntax would be :

"DELETE FROM Medicos WHERE nome= ' ".$cbnome." ' " 

without the * (asterisk)

The * is used for query tags as a wildcard for all fields in the table. In query delete you want to delete an entire line of record so there is no sense of using it there.

If it helps you!

Answer 2

Hello, Isabel!

In your combobox is sending the id value and in delete you are trying to delete by name.

 echo '<option value="'.$prod['txtid'].'">'.$prod['txtNome'].'</option>';

If you want to delete by name, then send the name in value

echo '<option value="'.$prod['txtNome'].'">'.$prod['txtNome'].'</option>';

Your code even works, but since it doesn’t find any name that matches the id you’re sending, then it doesn’t delete anything.

Then in your php you put the DELETE command:

DELETE FROM Medicos WHERE nome= '".$cbnome."' "

I believe that’s it.