mysqli::change_user
mysqli_change_user
(PHP 5, PHP 7, PHP 8)
mysqli::change_user -- mysqli_change_user — Changes the user of the specified database connection
Beschreibung
Objektorientierter Stil
$username
, string $password
, ?string $database
): boolProzeduraler Stil
Changes the user of the specified database connection and sets the current database.
In order to successfully change users a valid username
and
password
parameters must be provided and that user must have
sufficient permissions to access the desired database. If for any reason authorization
fails, the current user authentication will remain.
Parameter-Liste
-
mysql
-
Nur bei prozeduralem Aufruf: Ein von mysqli_connect() oder mysqli_init() zurückgegebenes mysqli-Objekt.
-
username
-
The MySQL user name.
-
password
-
The MySQL password.
-
database
-
The database to change to.
If desired, the
null
value may be passed resulting in only changing the user and not selecting a database. To select a database in this case use the mysqli_select_db() function.
Rückgabewerte
Gibt bei Erfolg true
zurück. Bei einem Fehler wird false
zurückgegeben.
Beispiele
Beispiel #1 mysqli::change_user() example
Objektorientierter Stil
<?php
/* connect database test */
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
/* Set Variable a */
$mysqli->query("SET @a:=1");
/* reset all and select a new database */
$mysqli->change_user("my_user", "my_password", "world");
if ($result = $mysqli->query("SELECT DATABASE()")) {
$row = $result->fetch_row();
printf("Default database: %s\n", $row[0]);
$result->close();
}
if ($result = $mysqli->query("SELECT @a")) {
$row = $result->fetch_row();
if ($row[0] === NULL) {
printf("Value of variable a is NULL\n");
}
$result->close();
}
/* close connection */
$mysqli->close();
?>
Prozeduraler Stil
<?php
/* connect database test */
$link = mysqli_connect("localhost", "my_user", "my_password", "test");
/* check connection */
if (!$link) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
/* Set Variable a */
mysqli_query($link, "SET @a:=1");
/* reset all and select a new database */
mysqli_change_user($link, "my_user", "my_password", "world");
if ($result = mysqli_query($link, "SELECT DATABASE()")) {
$row = mysqli_fetch_row($result);
printf("Default database: %s\n", $row[0]);
mysqli_free_result($result);
}
if ($result = mysqli_query($link, "SELECT @a")) {
$row = mysqli_fetch_row($result);
if ($row[0] === NULL) {
printf("Value of variable a is NULL\n");
}
mysqli_free_result($result);
}
/* close connection */
mysqli_close($link);
?>
Die obigen Bespiele erzeugen folgende Ausgabe:
Default database: world Value of variable a is NULL
Anmerkungen
Hinweis:
Using this command will always cause the current database connection to behave as if was a completely new database connection, regardless of if the operation was completed successfully. This reset includes performing a rollback on any active transactions, closing all temporary tables, and unlocking all locked tables.
Siehe auch
- mysqli_connect() - Alias von mysqli::__construct
- mysqli_select_db() - Selects the default database for database queries