Php Mysql 简明教程
PHP & MySQL - Select Database Example
PHP 使用 mysqli_select_db 函数来选择要执行查询的数据库。此函数接受两个参数,并成功时返回 TRUE,失败时返回 FALSE。
PHP uses mysqli_select_db function to select the database on which queries are to be performed. This function takes two parameters and returns TRUE on success or FALSE on failure.
Syntax
mysqli_select_db ( mysqli $link , string $dbname ) : bool
Sr.No. |
Parameter & Description |
1 |
$link Required - A link identifier returned by mysqli_connect() or mysqli_init(). |
2 |
$dbname Required - Name of the database to be connected. |
Example
尝试以下示例以选择数据库 −
Try the following example to select a database −
将以下示例复制粘贴为 mysql_example.php:
Copy and paste the following example as mysql_example.php −
<html>
<head>
<title>Selecting MySQL Database</title>
</head>
<body>
<?php
$dbhost = 'localhost';
$dbuser = 'root';
$dbpass = 'root@123';
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn ) {
die('Could not connect: ' . mysqli_error($conn));
}
echo 'Connected successfully<br />';
$retval = mysqli_select_db( $conn, 'TUTORIALS' );
if(! $retval ) {
die('Could not select database: ' . mysqli_error($conn));
}
echo "Database TUTORIALS selected successfully\n";
mysqli_close($conn);
?>
</body>
</html>