php連接mysql公共文件、操作mysql數據庫

//php連接mysql公共文件

<?php 
//數據庫配置信息
$db_host = "localhost";//主機名
$db_user = "admin";//用戶名
$db_pass = "admin";//密碼
$db_name = "tablename";//數據庫名
$charset = "utf8";//字符集

//php連接mysql服務器
if (!$link = @mysqli_connect($db_host, $db_user, $db_pass)) {
echo "<h2>數據庫連接失敗！</h2>";
die();
}
//選擇數據庫
if (!mysqli_select_db($link, $db_name)) {
echo "<h2>數據庫選擇失敗！</h2>";
die();
}
//設置字符集對象
mysqli_set_charset($link, $charset);

 

//php執行mysql語句

//定義sql語句
$sql = "SELECT * FROM tablename";
//執行結果
//$link=mysqli_connect($db_host, $db_user, $db_pass)連接數據庫成功后
$result = mysqli_query($link, $sql);
//結果導入到數組中
//MYSQLI_ASSOC為常量
$arrs = mysqli_fetch_all($result, MYSQLI_ASSOC) 
//獲取記錄數目
$records = mysqli_num_rows($result);

 mysqli_fetch_all

 

//mysql 查詢數據

$sql = "SELECT * FROM photos WHERE username = '$username' ORDER BY id DESC LIMIT {$startrow}, {$pagesize}";

//mysql 更新數據

$sql = "UPDATE photos SET hits = {$hits} WHERE imgsrc = {$src}";