mysqli::rollback
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.
mysqli::select_db
mysqli_select_db
(PHP 5)
mysqli::select_db -- mysqli_select_db — Selects the default database for database queries
설명
객체 기반 형식
bool mysqli::select_db
( string $dbname
)
절차식 형식
Selects the default database to be used when performing queries against the database connection.
Note:
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().
반환값
성공할 경우 TRUE를, 실패할 경우 FALSE를 반환합니다.
예제
Example #1 mysqli::select_db() example
객체 기반 형식
<?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();
?>
절차식 형식
<?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);
?>
위 예제들의 출력:
Default database is test. Default database is world.
참고
- mysqli_connect() - 별칭: mysqli::__construct
- mysqli_real_connect() - Opens a connection to a mysql server
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User Contributed Notes
mysqli::select_db
pjasiulewicz at gmail dot com
27-Mar-2011 02:30