w3resource

PHP mysqli: change_user() Function

mysqli_change_user() function / mysqli::change_user

The mysqli_change_user() function / mysqli::change_user changes the user of the specified database connection, and sets the current database.

Syntax:

Object oriented style

bool mysqli::change_user ( string $user , string $password , string $database )

Procedural style

bool mysqli_change_user ( mysqli $link , string $user , string $password , string $database )

Usage: Procedural style

mysqli_change_user(connection,username,password,dbname);

Parameter:

Name Description Required/Optional
connection Specifies the MySQL connection to use. Required
username Specifies the MySQL username Required
password Specifies the MySQL password Required
dbname Specifies the database to change to Required

Return value:

Returns TRUE on success or FALSE on failure.

Version: PHP 5, PHP 7

Example of object oriented style:

<?php
/* connect database test */
$mysqli = new mysqli("localhost", "user1", "datasoft123", "hr");


/* 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();
?>

Output:

Default database: hr Value of variable a is NULL

Example of procedural style:

<?php
/* connect database test */
$link = mysqli_connect("localhost", "user1", "datasoft123", "hr");

/* 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, "user1", "datasoft123", "hr");

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);
?>

Output:

Default database: hr Value of variable a is NULL

See also

PHP Function Reference

Previous: begin_transaction
Next: character_set_name



Follow us on Facebook and Twitter for latest update.

PHP: Tips of the Day

To use the constant simply use its name:

Example:

if (EARTH_IS_FLAT) {
 print "Earth is flat";
}
print APP_ENV_UPPERCASE;

Output:



or if you don't know the name of the constant in advance, use the constant function:


// this code is equivalent to the above code
$const1 = "EARTH_IS_FLAT";
$const2 = "APP_ENV_UPPERCASE";
if (constant($const1)) {
 print "Earth is flat";
}
print constant($const2);



Output:




 


























We are closing our Disqus commenting system for some maintenanace issues. You may write to us at reach[at]yahoo[dot]com or visit us
at Facebook