(PHP 5, PHP 7)
mysqli::select_db -- mysqli_select_db — 选锟斤拷锟斤拷锟斤拷锟斤拷锟捷匡拷锟窖拷锟侥拷锟斤拷锟斤拷菘锟�
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$dbname
) : bool锟斤拷锟教伙拷锟斤拷锟�
锟斤拷员锟斤拷锟斤拷锟斤拷菘锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷菘锟斤拷询锟斤拷默锟斤拷锟斤拷锟捷库。
Note:
锟斤拷锟斤拷锟斤拷应锟斤拷只锟斤拷锟斤拷锟节改变本锟斤拷锟斤拷锟接碉拷锟斤拷锟捷库，锟斤拷也锟斤拷锟斤拷mysqli_connect()锟斤拷锟侥革拷锟斤拷锟斤拷确锟斤拷默锟斤拷锟斤拷锟捷库。
link锟斤拷锟皆癸拷锟教伙拷锟斤拷式锟斤拷锟斤拷mysqli_connect() 锟斤拷 mysqli_init() 锟斤拷锟截碉拷锟斤拷锟接憋拷识锟斤拷
dbname锟斤拷锟捷匡拷锟斤拷锟斤拷
锟缴癸拷时锟斤拷锟斤拷 TRUE锟斤拷 锟斤拷锟斤拷锟斤拷失锟斤拷时锟斤拷锟斤拷 FALSE锟斤拷
Example #1 mysqli::select_db() example
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<?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();
?>
锟斤拷锟教伙拷锟斤拷锟�
<?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);
?>
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Default database is test. Default database is world.