(PHP 5, PHP 7, PHP 8)
mysqli::change_user -- mysqli_change_user — Changes the user of the specified database connection
Object-oriented style
Procedural style
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.
mysql
Procedural style only: A mysqli object returned by mysqli_connect() or mysqli_init()
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.
If mysqli error reporting is enabled (MYSQLI_REPORT_ERROR
) and the requested operation fails, a warning is generated. If, in addition, the mode is set to MYSQLI_REPORT_STRICT
, a mysqli_sql_exception is thrown instead.
Example #1 mysqli::change_user() example
Object-oriented style
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$mysqli->query("SET @a:=1");
$mysqli->change_user("my_user", "my_password", "world");
if ($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();
}
$mysqli->close();
?>
Procedural style
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "test");
if (!$link) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
mysqli_query($link, "SET @a:=1");
mysqli_change_user($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);
}
mysqli_close($link);
?>
The above examples will output:
Default database: world Value of variable a is NULL
Note:
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.