Note that in the second example, if the database "world" does not exist, the database selected does not change. You may need to add additional code to ensure that you are connected to the correct database.
mysqli::select_db
mysqli_select_db
(PHP 5, PHP 7)
mysqli::select_db -- mysqli_select_db — Selects the default database for database queries
Açıklama
Nesne yönelimli kullanım
public mysqli::select_db(string
$database): boolYordamsal kullanım
Selects the default database to be used when performing queries against the database connection.
Bilginize:
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().
Değiştirgeler
-
bağlantı -
Sadece yordamsal tarz: mysqli_connect() veya mysqli_init() işlevinden dönen bir mysqli nesnesi.
-
database -
The database name.
Dönen Değerler
Başarı durumunda true, başarısızlık durumunda false döner.
Örnekler
Örnek 1 mysqli::select_db() example
Nesne yönelimli kullanım
<?php
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");
/* get the name of the current default database */
$result = $mysqli->query("SELECT DATABASE()");
$row = $result->fetch_row();
printf("Default database is %s.\n", $row[0]);
/* change default database to "world" */
$mysqli->select_db("world");
/* get the name of the current default database */
$result = $mysqli->query("SELECT DATABASE()");
$row = $result->fetch_row();
printf("Default database is %s.\n", $row[0]);
Yordamsal kullanım
<?php
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$link = mysqli_connect("localhost", "my_user", "my_password", "test");
/* get the name of the current default database */
$result = mysqli_query($link, "SELECT DATABASE()");
$row = mysqli_fetch_row($result);
printf("Default database is %s.\n", $row[0]);
/* change default database to "world" */
mysqli_select_db($link, "world");
/* get the name of the current default database */
$result = mysqli_query($link, "SELECT DATABASE()");
$row = mysqli_fetch_row($result);
printf("Default database is %s.\n", $row[0]);
Yukarıdaki örneklerin çıktısı:
Default database is test. Default database is world.
Ayrıca Bakınız
- mysqli_connect() - Takma Adı: mysqli::__construct
- mysqli_real_connect() - Opens a connection to a mysql server
add a note
User Contributed Notes 2 notes
hwalker1 at btopenworld dot com ¶
10 years ago
pjasiulewicz at gmail dot com ¶
13 years ago
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.
