mysqli::select_db

mysqli_select_db

(PHP 5)

mysqli::select_db -- mysqli_select_db — Selects the default database for database queries

Descrição

Estilo orientado a objetos

bool mysqli::select_db ( string $dbname )

Estilo de procedimentos

bool mysqli_select_db ( mysqli $link , string $dbname )

Selects the default database to be used when performing queries against the database connection.

Nota:
This function should only be used to change the default database for the connection. You can select the default database with 4th parameter in mysqli_connect().

Parâmetros

link: Apenas para estilo de procedimento: Um identificador de conexão retornado por mysqli_connect() or mysqli_init()
dbname: The database name.

Valor Retornado

Retorna TRUE em caso de sucesso ou FALSE em falhas.

Exemplos

Exemplo #1 mysqli::select_db() example

Estilo orientado a objetos


<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

/* return name of current default database */
if ($result = $mysqli->query("SELECT DATABASE()")) {
    $row = $result->fetch_row();
    printf("Default database is %s.\n", $row[0]);
    $result->close();
}

/* change db to world db */
$mysqli->select_db("world");

/* return name of current default database */
if ($result = $mysqli->query("SELECT DATABASE()")) {
    $row = $result->fetch_row();
    printf("Default database is %s.\n", $row[0]);
    $result->close();
}

$mysqli->close();
?>

Estilo de procedimentos


<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "test");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

/* return name of current default database */
if ($result = mysqli_query($link, "SELECT DATABASE()")) {
    $row = mysqli_fetch_row($result);
    printf("Default database is %s.\n", $row[0]);
    mysqli_free_result($result);
}

/* change db to world db */
mysqli_select_db($link, "world");

/* return name of current default database */
if ($result = mysqli_query($link, "SELECT DATABASE()")) {
    $row = mysqli_fetch_row($result);
    printf("Default database is %s.\n", $row[0]);
    mysqli_free_result($result);
}

mysqli_close($link);
?>

The above examples will output:

Default database is test.
Default database is world.

Veja Também

mysqli_connect() - Sinônimo de mysqli::__construct
mysqli_real_connect() - Opens a connection to a mysql server

add a note User Contributed Notes mysqli::select_db

pjasiulewicz at gmail dot com 27-Mar-2011 08:30


In some situations its useful to use this function for changing databases in general. We've tested it in production environment and it seams to be faster with switching databases than creating new connections.

add a note