Just to clarify this note in the Manual regarding this function:
"Note: When using mysqli_stmt_execute(), the mysqli_stmt_fetch() function must be used to fetch the data prior to performing any additional queries."
This is because this function DOES NOT store the result set on the client side so you have to fetch everything in the result set or else you risk major errors.
If you however use the function mysqli_stmt_store_result immediately after you use this function, you are forcing the result set to be stored on the client side and thus it is safe to issue extra queries before fetching all the data.
This is where you really have to make a choice regarding on your application's priorities. If you know your result set is memory hefty, then its a good idea not to store it on the client side so you don't run in any errors regarding unavailable memory on the server. But this also means your not going to do a lot of calculations on the result set or else you will prevent any other usage of the table to which the result set came from until you fetched it all.
If your going to do a lot of calculations or your result set is not memory hefty, its probably a good idea to store it on the client side.
Most of these problems can easily be solved if you have a lot of memory available on your server but thats usually not the case for those on shared hosting.
An intelligent way to counter this problem if your on a shared host is to be smart in the way you design your queries. Try to limit the result set if you know you will be fetching memory hefty result sets.
Test different alternatives for your application and see what works best for you under different conditions.
Good Luck,
mysqli_stmt::execute
mysqli_stmt_execute
(PHP 5, PHP 7)
mysqli_stmt::execute -- mysqli_stmt_execute — Exécute une requête préparée
Description
Style orienté objet
public mysqli_stmt::execute
( void
) : bool
Style procédural
Exécute une requête qui a été préalablement préparée en utilisant la
fonction mysqli_prepare(), grâce à la ressource
stmt. Lors de l'exécution, toutes les
variables de la requête seront remplacées par les données appropriées.
Si la requête est UPDATE, DELETE ou INSERT, le nombre total de lignes affectées est disponible via la fonction mysqli_stmt_affected_rows(). De la même façon, si la fonction génère un résultat, il sera disponible via la fonction mysqli_stmt_fetch().
Note:
Lors de l'utilisation de mysqli_stmt_execute(), mysqli_stmt_fetch() doit être utilisée pour lire les données avant de lancer une autre requête.
Liste de paramètres
-
stmt -
Style procédural uniquement : Un identifiant de requête retourné par la fonction mysqli_stmt_init().
Valeurs de retour
Cette fonction retourne TRUE en cas de succès ou FALSE si une erreur survient.
Exemples
Exemple #1 Style orienté objet
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* Vérifie la connexion */
if (mysqli_connect_errno()) {
printf("Échec de la connexion : %s\n", mysqli_connect_error());
exit();
}
$mysqli->query("CREATE TABLE myCity LIKE City");
/* Préparation de la commande d'insertion */
$query = "INSERT INTO myCity (Name, CountryCode, District) VALUES (?,?,?)";
$stmt = $mysqli->prepare($query);
$stmt->bind_param("sss", $val1, $val2, $val3);
$val1 = 'Stuttgart';
$val2 = 'DEU';
$val3 = 'Baden-Wuerttemberg';
/* Exécute la requête */
$stmt->execute();
$val1 = 'Bordeaux';
$val2 = 'FRA';
$val3 = 'Aquitaine';
/* Exécute la requête */
$stmt->execute();
/* Ferme la requête */
$stmt->close();
/* Récupère toutes les lignes de la table myCity */
$query = "SELECT Name, CountryCode, District FROM myCity";
if ($result = $mysqli->query($query)) {
while ($row = $result->fetch_row()) {
printf("%s (%s,%s)\n", $row[0], $row[1], $row[2]);
}
/* Libère le résultat */
$result->close();
}
/* Efface la table */
$mysqli->query("DROP TABLE myCity");
/* Ferme la connexion */
$mysqli->close();
?>
Exemple #2 Style procédural
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* Vérifie la connexion */
if (mysqli_connect_errno()) {
printf("Échec de la connexion : %s\n", mysqli_connect_error());
exit();
}
mysqli_query($link, "CREATE TABLE myCity LIKE City");
/* Préparation de la commande d'insertion */
$query = "INSERT INTO myCity (Name, CountryCode, District) VALUES (?,?,?)";
$stmt = mysqli_prepare($link, $query);
mysqli_stmt_bind_param($stmt, "sss", $val1, $val2, $val3);
$val1 = 'Stuttgart';
$val2 = 'DEU';
$val3 = 'Baden-Wuerttemberg';
/* Exécute la requête */
mysqli_stmt_execute($stmt);
$val1 = 'Bordeaux';
$val2 = 'FRA';
$val3 = 'Aquitaine';
/* Exécute la requête */
mysqli_stmt_execute($stmt);
/* Ferme la requête */
mysqli_stmt_close($stmt);
/* Récupère toutes les lignes de la table myCity */
$query = "SELECT Name, CountryCode, District FROM myCity";
if ($result = mysqli_query($link, $query)) {
while ($row = mysqli_fetch_row($result)) {
printf("%s (%s,%s)\n", $row[0], $row[1], $row[2]);
}
/* Libère le résultat */
mysqli_free_result($result);
}
/* Efface la table */
mysqli_query($link, "DROP TABLE myCity");
/* Ferme la connexion */
mysqli_close($link);
?>
Les exemples ci-dessus vont afficher :
Stuttgart (DEU,Baden-Wuerttemberg) Bordeaux (FRA,Aquitaine)
Voir aussi
- mysqli_prepare() - Prépare une requête SQL pour l'exécution
- mysqli_stmt_bind_param() - Lie des variables à une requête MySQL
- mysqli_stmt_get_result() - Récupère un jeu de résultats depuis une requête préparée
add a note
User Contributed Notes 3 notes
Typer85 at gmail dot com ¶
13 years ago
vedran-b at email dot htnet dot hr ¶
9 years ago
After the stmt->execute() function is called the variable "$X" that was storing the bind param e.g.
$stmt->bind_param("i", $X);
gets set to 0.
So don't try to use it for something else later... like me ...for $_session key coz you'll get crazy..... like me...
p.s. $_session keys starting with nums get discarded.
andrey at php dot net ¶
14 years ago
If you select LOBs use the following order of execution or you risk mysqli allocating more memory that actually used
1)prepare()
2)execute()
3)store_result()
4)bind_result()
If you skip 3) or exchange 3) and 4) then mysqli will allocate memory for the maximal length of the column which is 255 for tinyblob, 64k for blob(still ok), 16MByte for MEDIUMBLOB - quite a lot and 4G for LONGBLOB (good if you have so much memory). Queries which use this order a bit slower when there is a LOB but this is the price of not having memory exhaustion in seconds.
