INSERT INTO doesn't write anything in the database - php

Question

Basically, we are trying to add some values in a database. We are doing it using a GET command to get the value called "valeur" and writing this in the database. However it is not working, the values are not added to the database
<?php
try
{ // connection a la base de donnees
// connection to mySQL
$bdd = new
PDO('mysql:localhost;dbname=test1', 'root', '');
}
catch(Exception $e) //in case of error, display it and stop everything
{
die('Erreur : '.$e->getMessage());
}
if (isset($_GET['temp1'])) // test if the variable exists
{
$_GET['temp1'] = floatval($_GET['temp1']);
echo ('donnee ' .$_GET["temp1"]. ' en cours d\'ecriture</br>');
$bdd->exec('INSERT INTO temp (valeur) VALUES('.$_GET["temp1"].')');
echo ('donnee ' .$_GET['temp1']. ' ecrite!');
}
?>
If we put a value in (in our case) http://localhost/test1/add.php?temp1=(thevalue) then it should be inserted into our table called temp in the column "valeur". Instead, it doesn't write anything.
Edit : We are using PHP version 5.6.19 and MySQL 5.7.11 and WAMPserver
EDIT2: I have finally resolved the problem, though I have no idea how.
Php looks fun

Answer 1

You should assign a variable for the SQL query for debugging target.
And echo to print how is your query string. After that, you paste your $query in SQL tab at Phpmyadmin to know what is your error.
$query = "INSERT INTO temp (valeur) VALUES('.$_GET['temp1'].')";
echo $query;

Answer 2

As you are using PDO it makes sense to utilise some of the strengths of it - primarily in this case prepared statements and bound parameters to make the sql much safer from malicious users.
If you separate the database connection from the remaining code you have a database connection which can be used elsewhere quickly and easily simply by including it at runtime, so the first piece of code below could be the db connection file.
( I see you have solved the problem yourself just before posting this... )
<?php
/*******************
dbo-conn.php
*/
try{
$options=array(
PDO::ATTR_CURSOR => PDO::CURSOR_SCROLL,
PDO::ATTR_PERSISTENT => false,
PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => true,
PDO::ATTR_EMULATE_PREPARES => true,
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'utf8mb4\' COLLATE \'utf8mb4_general_ci\', ##sql_mode = STRICT_ALL_TABLES, ##foreign_key_checks = 1'
);
$dbuser='root';
$dbpwd='';
$bdd=new PDO( 'mysql:host=localhost;dbname=test1;port=3306;charset=UTF8', $dbuser, $dbpwd, $options );
}catch( PDOException $e ){
exit( $e->getMessage() );
}
?>
On the page that does the database inserts
<?php
try{
# test that the variable is set and available...
if( !empty( $_GET['temp1'] ) ){
# rudimentary check for number
if( !is_numeric( $_GET['temp1'] ) )throw new Exception( sprintf( 'Supplied parameter "%s" does not appear to be a number', $_GET['temp1'] ) );
$valeur = $_GET['temp1'];
# include the db connection
# the path used here depends where the file `dbo-conn.php` is saved
# - this assumes the same directory
require 'dbo-conn.php';
# generate sql & prepared statement
$sql='insert into `temp` ( `valeur` ) values ( :valeur )';
$stmt = $bdd->prepare( $sql );
# check the prepared statement was created ok before attempting to execute it
if( !$stmt ) throw new Exception( 'Failed to prepare sql "INSERT" query'
# bind the placeholder to the supplied user input
$stmt->bindParam( ':valeur', $valeur, PDO::PARAM_STR );
# commit the query
$result = $stmt->execute();
if( !$result )throw new Exception( 'oops! something went wrong' );
# display a message to the user
printf('donnee %s ecrite!', $valeur );
}
}catch( Exception $e ){
exit( sprintf( 'Erreur: %s', $e->getMessage() ) );
}
?>